chore: staticcheck and gofmt cleanups

37 files changed, 67 insertions, 539 deletions

diff --git a/internal/admin/api_colors.go b/internal/admin/api_colors.go
index 876656d..b57ad82 100644
--- a/internal/admin/api_colors.go
+++ b/internal/admin/api_colors.go
@@ -3,7 +3,6 @@ package admin
 import (
 	"net/http"
 	"os"
-	"sort"
 	"strings"
 
 	"gopkg.in/yaml.v3"
@@ -185,11 +184,6 @@ func knownConstantColor(name string) bool {
 	return false
 }
 
-// knownColor returns true if name is editable in either section.
-func knownColor(name string) bool {
-	return knownPlayerColor(name) || knownConstantColor(name)
-}
-
 // seg is a small constructor helper for the inline preview builder.
 func seg(t, cat string) colorSegment {
 	return colorSegment{T: t, C: cat}
@@ -280,7 +274,6 @@ func buildPreview() []colorSection {
 			ln(seg("Oh dear, you are dead!", "death")),
 			txt(""),
 			txt(""),
-
 		},
 	})
 
@@ -479,20 +472,20 @@ func (s *AdminServer) getColors(w http.ResponseWriter, _ *http.Request) {
 	}
 
 	writeJSON(w, map[string]any{
-		"colors":                 live,
-		"default_colors":         def,
-		"categories":             colorCategories,
-		"constant_colors":        liveConst,
+		"colors":                  live,
+		"default_colors":          def,
+		"categories":              colorCategories,
+		"constant_colors":         liveConst,
 		"default_constant_colors": defConst,
-		"constant_categories":    constantCategories,
-		"preview":                buildPreview(),
+		"constant_categories":     constantCategories,
+		"preview":                 buildPreview(),
 	})
 }
 
 func (s *AdminServer) saveColors(w http.ResponseWriter, r *http.Request) {
 	var body struct {
-		Colors          map[string]string `json:"colors"`
-		ConstantColors  map[string]string `json:"constant_colors"`
+		Colors         map[string]string `json:"colors"`
+		ConstantColors map[string]string `json:"constant_colors"`
 	}
 	if err := readJSON(r, &body); err != nil {
 		writeJSONError(w, "invalid request body", http.StatusBadRequest)
@@ -593,14 +586,3 @@ func (s *AdminServer) writeConfigFile() error {
 	}
 	return os.WriteFile(s.configPath, out, 0644)
 }
-
-// sortedKeys is a small helper retained in case future code wants a stable
-// iteration order over the category names.
-func sortedKeys(m map[string]string) []string {
-	keys := make([]string, 0, len(m))
-	for k := range m {
-		keys = append(keys, k)
-	}
-	sort.Strings(keys)
-	return keys
-}
diff --git a/internal/admin/api_colors_test.go b/internal/admin/api_colors_test.go
index 1f5d3eb..53c68b1 100644
--- a/internal/admin/api_colors_test.go
+++ b/internal/admin/api_colors_test.go
@@ -225,4 +225,4 @@ func TestColorsPreviewExhaustive(t *testing.T) {
 		}
 	}
 	_ = io.Discard
-}
\ No newline at end of file
+}
diff --git a/internal/admin/api_room_courses.go b/internal/admin/api_room_courses.go
index 47e4d8c..b8f334e 100644
--- a/internal/admin/api_room_courses.go
+++ b/internal/admin/api_room_courses.go
@@ -105,19 +105,6 @@ func toInt(v any) int {
 	return 0
 }
 
-// toFloat64 coerces yaml-decoded numbers to float64.
-func toFloat64(v any) float64 {
-	switch x := v.(type) {
-	case int:
-		return float64(x)
-	case int64:
-		return float64(x)
-	case float64:
-		return x
-	}
-	return 0
-}
-
 // indexOfObstacleForRoom returns the index of the obstacle whose room_id
 // matches roomID, or -1 if none.
 func indexOfObstacleForRoom(obstacles []map[string]any, roomID int) int {
@@ -515,39 +502,6 @@ func (s *AdminServer) loadRoomMapByID(roomID int) (map[string]any, []byte, strin
 	return m, data, path, nil
 }
 
-// saveRoomMapByID writes a room map back to disk and pushes an undo entry.
-func (s *AdminServer) saveRoomMapByID(roomID int, m map[string]any, desc string) error {
-	path, ok := s.world.GetRoomPath(roomID)
-	if !ok {
-		return fmt.Errorf("room %d not found", roomID)
-	}
-	oldContent, _ := snapshotFile(path)
-	newContent, err := writeMapAsYAML(path, m)
-	if err != nil {
-		return err
-	}
-	s.undoStack.Push(ChangeDesc{
-		Description: desc,
-		FilePath:    path,
-		OldContent:  oldContent,
-		NewContent:  newContent,
-	})
-	return nil
-}
-
-// removeExit deletes an exit by direction. Returns true if it existed.
-func removeExit(m map[string]any, dir string) bool {
-	ex, ok := m["exits"].(map[string]any)
-	if !ok {
-		return false
-	}
-	if _, exists := ex[dir]; exists {
-		delete(ex, dir)
-		return true
-	}
-	return false
-}
-
 // exitTargetRoom returns the target room ID of an exit value (scalar or map).
 func exitTargetRoom(v any) int {
 	switch x := v.(type) {
@@ -563,16 +517,6 @@ func exitTargetRoom(v any) int {
 	return 0
 }
 
-// exitIsAlwaysBlocked returns whether an exit value carries always_blocked: true.
-func exitIsAlwaysBlocked(v any) bool {
-	if mm, ok := v.(map[string]any); ok {
-		if h, ok := mm["always_blocked"]; ok {
-			return h == true
-		}
-	}
-	return false
-}
-
 // isHorizontalDir returns whether d is one of the 8 horizontal directions.
 func isHorizontalDir(d string) bool {
 	for _, h := range horizontalExitDirs {
diff --git a/internal/admin/api_rooms.go b/internal/admin/api_rooms.go
index 01b7b9a..8ee16a5 100644
--- a/internal/admin/api_rooms.go
+++ b/internal/admin/api_rooms.go
@@ -131,7 +131,7 @@ func (s *AdminServer) handleRooms(w http.ResponseWriter, r *http.Request) {
 					conflicts++
 				})
 				if conflicts > 0 {
-					writeJSON(w, map[string]any{"error": fmt.Sprintf("Add Next Step: that grid spot is already occupied — room would cause map overlap")})
+					writeJSON(w, map[string]any{"error": "Add Next Step: that grid spot is already occupied — room would cause map overlap"})
 					return
 				}
 			} else {
diff --git a/internal/admin/undo.go b/internal/admin/undo.go
index 98d8d9a..51610f8 100644
--- a/internal/admin/undo.go
+++ b/internal/admin/undo.go
@@ -414,73 +414,6 @@ func (us *UndoStack) save() {
 	}
 }
 
-func (us *UndoStack) load() {
-	data, err := os.ReadFile(us.filePath)
-	if err != nil {
-		return
-	}
-	log.Printf("undo: loaded history from %s", us.filePath)
-	type extraEntry struct {
-		FilePath    string `json:"file_path"`
-		NewFilePath string `json:"new_file_path,omitempty"`
-		OldContent  string `json:"old_content"`
-		NewContent  string `json:"new_content"`
-		IsDelete    bool   `json:"is_delete,omitempty"`
-		IsCreate    bool   `json:"is_create,omitempty"`
-	}
-	type entry struct {
-		Time        string       `json:"time"`
-		Description string       `json:"description"`
-		FilePath    string       `json:"file_path"`
-		NewFilePath string       `json:"new_file_path,omitempty"`
-		OldContent  string       `json:"old_content"`
-		NewContent  string       `json:"new_content"`
-		IsDelete    bool         `json:"is_delete"`
-		IsCreate    bool         `json:"is_create"`
-		ExtraFiles  []extraEntry `json:"extra_files,omitempty"`
-		IDMap       map[int]int  `json:"id_map,omitempty"`
-	}
-	var saveData struct {
-		History []entry `json:"history"`
-		Redo    []entry `json:"redo"`
-	}
-	if err := json.Unmarshal(data, &saveData); err != nil {
-		log.Printf("undo: failed to unmarshal history: %v", err)
-		return
-	}
-	fromEntries := func(entries []entry) []ChangeDesc {
-		var changes []ChangeDesc
-		for _, e := range entries {
-			var extra []ExtraFile
-			for _, ef := range e.ExtraFiles {
-				extra = append(extra, ExtraFile{
-					FilePath:    ef.FilePath,
-					NewFilePath: ef.NewFilePath,
-					OldContent:  []byte(ef.OldContent),
-					NewContent:  []byte(ef.NewContent),
-					IsDelete:    ef.IsDelete,
-					IsCreate:    ef.IsCreate,
-				})
-			}
-			changes = append(changes, ChangeDesc{
-				Time:        e.Time,
-				Description: e.Description,
-				FilePath:    e.FilePath,
-				NewFilePath: e.NewFilePath,
-				OldContent:  []byte(e.OldContent),
-				NewContent:  []byte(e.NewContent),
-				IsDelete:    e.IsDelete,
-				IsCreate:    e.IsCreate,
-				ExtraFiles:  extra,
-				IDMap:       e.IDMap,
-			})
-		}
-		return changes
-	}
-	us.history = fromEntries(saveData.History)
-	log.Printf("undo: loaded %d history entries", len(us.history))
-}
-
 func (us *UndoStack) Clear() {
 	us.mu.Lock()
 	defer us.mu.Unlock()
diff --git a/internal/admin/xterm_to_css.go b/internal/admin/xterm_to_css.go
index 098ce62..6c1fda4 100644
--- a/internal/admin/xterm_to_css.go
+++ b/internal/admin/xterm_to_css.go
@@ -25,16 +25,3 @@ func XtermColorForCSS(idx int) string {
 	r, g, b := color.Xterm256ToRGB(idx)
 	return fmt.Sprintf("#%02x%02x%02x", r, g, b)
 }
-
-func xtermColorList() []map[string]any {
-	var list []map[string]any
-	for i := 0; i < 256; i++ {
-		r, g, b := color.Xterm256ToRGB(i)
-		list = append(list, map[string]any{
-			"index": i,
-			"hex":   fmt.Sprintf("%02X%02X%02X", r, g, b),
-			"color": fmt.Sprintf("#%02x%02x%02x", r, g, b),
-		})
-	}
-	return list
-}
diff --git a/internal/admin/yaml_util.go b/internal/admin/yaml_util.go
index 9ef8058..6ea6692 100644
--- a/internal/admin/yaml_util.go
+++ b/internal/admin/yaml_util.go
@@ -142,23 +142,6 @@ func listYAMLTree(dataDir, subdir string) (*YAMLTree, error) {
 	return tree, nil
 }
 
-func listYAMLFilesDeep(dataDir, subdir string) ([]string, error) {
-	var ids []string
-	base := filepath.Join(dataDir, subdir)
-	err := filepath.WalkDir(base, func(path string, d os.DirEntry, err error) error {
-		if err != nil {
-			return err
-		}
-		if !d.IsDir() && filepath.Ext(d.Name()) == ".yaml" {
-			rel, _ := filepath.Rel(base, path)
-			id := rel[:len(rel)-5]
-			ids = append(ids, id)
-		}
-		return nil
-	})
-	return ids, err
-}
-
 func backupFile(path string) []byte {
 	data, err := os.ReadFile(path)
 	if err != nil {
diff --git a/internal/casino/slots.go b/internal/casino/slots.go
index c519293..075050c 100644
--- a/internal/casino/slots.go
+++ b/internal/casino/slots.go
@@ -71,15 +71,6 @@ func (p SlotProfile) Normalize() SlotProfile {
 	return p
 }
 
-func (p SlotProfile) symbol(id string) *SlotSymbol {
-	for i := range p.Symbols {
-		if p.Symbols[i].ID == id {
-			return &p.Symbols[i]
-		}
-	}
-	return nil
-}
-
 func generateSlotSpinWithProfile(rng *rand.Rand, bet int, profile SlotProfile) *SlotSpin {
 	p := profile.Normalize()
 	spin := &SlotSpin{}
diff --git a/internal/config/config.go b/internal/config/config.go
index 72c1c87..ffc4e50 100644
--- a/internal/config/config.go
+++ b/internal/config/config.go
@@ -103,12 +103,12 @@ func DefaultConstantColors() ColorsConfig {
 		"task_bar_low":  "43",
 
 		// Score-panel other bars and tech/buff indicators (cmd_score.go).
-		"battery_bar":         "6E",
-		"run_energy_bar":      "6C",
-		"active_tech_on":      "6C",
-		"active_tech_status":  "6C",
-		"active_tech_stat":    "6E",
-		"score_max_value":     "FA",
+		"battery_bar":        "6E",
+		"run_energy_bar":     "6C",
+		"active_tech_on":     "6C",
+		"active_tech_status": "6C",
+		"active_tech_stat":   "6E",
+		"score_max_value":    "FA",
 
 		// Skill-level tier color on the score panel (cmd_score.go).
 		"skill_lvl_max":  "B4",
@@ -120,7 +120,7 @@ func DefaultConstantColors() ColorsConfig {
 		// Level-difference band on mobs/players (render_color.go).
 		"level_diff_equal":      "FA",
 		"level_diff_up_small":   "B3",
-		"level_diff_up_big":      "A7",
+		"level_diff_up_big":     "A7",
 		"level_diff_down_small": "6E",
 		"level_diff_down_big":   "41",
 
@@ -133,11 +133,11 @@ func DefaultConstantColors() ColorsConfig {
 
 		// Shared table-heading chrome (cmd_skills.go, cmd_mods.go,
 		// cmd_option.go, cmd_aps.go).
-		"table_header_label": "49",
-		"table_header_value": "FA",
+		"table_header_label":  "49",
+		"table_header_value":  "FA",
 		"table_header_detail": "F5",
-		"table_header_xp":    "B3",
-		"table_header_desc":  "FF",
+		"table_header_xp":     "B3",
+		"table_header_desc":   "FF",
 
 		// APS / look inline accents.
 		"aps_here":        "6C",
diff --git a/internal/engine/tick.go b/internal/engine/tick.go
index 74b1dcf..63ee6af 100644
--- a/internal/engine/tick.go
+++ b/internal/engine/tick.go
@@ -99,8 +99,11 @@ func (e *Engine) Stop() {
 // before owned state is saved.
 func (e *Engine) StopAndWait() {
 	e.Stop()
+	// Join any in-flight tick: processTick holds tickMu for its whole body,
+	// so acquiring the mutex blocks until the running callback completes;
+	// holding it until return keeps that guarantee for the caller.
 	e.tickMu.Lock()
-	e.tickMu.Unlock()
+	defer e.tickMu.Unlock()
 }
 
 // Tick fires every due subscriber synchronously and returns. Subscribers
diff --git a/internal/game/account_txn.go b/internal/game/account_txn.go
index 2ed62bb..25cbcdb 100644
--- a/internal/game/account_txn.go
+++ b/internal/game/account_txn.go
@@ -109,11 +109,6 @@ func (g *Game) backfillCharacterIDs() {
 	}
 }
 
-// canonicAccount returns the account name in its canonical on-disk form.
-func (g *Game) canonicalAccount(name string) (string, error) {
-	return g.AccountStore.FindAccount(name)
-}
-
 // canonicChar returns the character name in its canonical on-disk form.
 func (g *Game) canonicalChar(name string) (string, error) {
 	return g.AccountStore.FindCharacter(name)
diff --git a/internal/game/act_burn.go b/internal/game/act_burn.go
index c24d3d7..b310145 100644
--- a/internal/game/act_burn.go
+++ b/internal/game/act_burn.go
@@ -145,7 +145,7 @@ func (g *Game) startStoke(sess *net.Session, p *player.Player, itemID string) {
 
 	logDef, err := g.ItemStore.Load(itemID)
 	if err != nil || logDef.BurnTicks <= 0 {
-		sess.WriteLine(fmt.Sprintf("You can't stoke the fire with that."))
+		sess.WriteLine("You can't stoke the fire with that.")
 		return
 	}
 
diff --git a/internal/game/act_farm.go b/internal/game/act_farm.go
index 8ed0d1b..cc7ddc4 100644
--- a/internal/game/act_farm.go
+++ b/internal/game/act_farm.go
@@ -456,55 +456,6 @@ func (g *Game) toolShedLookSuffix(p *player.Player) string {
 	return fmt.Sprintf("Inside: %s.", strings.Join(stored, ", "))
 }
 
-func (g *Game) farmMatchPrefix(p *player.Player, input string) (prefix string, defID string, index int) {
-	objInstances := g.World.AllObjInstances(p.RoomID)
-	if len(objInstances) == 0 {
-		return "", "", -1
-	}
-
-	type indexedFarm struct {
-		prefix string
-		defID  string
-		index  int
-		name   string
-	}
-	var farms []indexedFarm
-
-	for _, obj := range objInstances {
-		if !farmPatchDefIDs[obj.DefID] {
-			continue
-		}
-		pref := farmFlagPrefix(obj.DefID, obj.Index)
-		if pref == "" {
-			continue
-		}
-		var name string
-		if def, err := g.ObjectStore.Load(obj.DefID); err == nil {
-			name = def.Name
-		} else {
-			name = obj.DefID
-		}
-		farms = append(farms, indexedFarm{prefix: pref, defID: obj.DefID, index: obj.Index, name: name})
-	}
-
-	if len(farms) == 0 {
-		return "", "", -1
-	}
-
-	if input == "" {
-		return farms[0].prefix, farms[0].defID, farms[0].index
-	}
-
-	lower := strings.ToLower(input)
-	for _, f := range farms {
-		if strings.Contains(lower, strings.ToLower(f.name)) || behavior.WordPrefixMatch(lower, f.name) {
-			return f.prefix, f.defID, f.index
-		}
-	}
-
-	return "", "", -1
-}
-
 func (g *Game) farmObjSuffix(p *player.Player, defID string, index int) string {
 	if defID == "tool_shed" {
 		return g.toolShedLookSuffix(p)
@@ -559,7 +510,7 @@ func (g *Game) showFarmPatches(sess *net.Session, p *player.Player) []string {
 		if weeds {
 			displays = append(displays, farmDisplay{
 				name: fmt.Sprintf("%s%s", patchName, idxStr),
-				line: fmt.Sprintf("overgrown with weeds"),
+				line: "overgrown with weeds",
 			})
 			continue
 		}
@@ -568,7 +519,7 @@ func (g *Game) showFarmPatches(sess *net.Session, p *player.Player) []string {
 		if seedID == "" {
 			displays = append(displays, farmDisplay{
 				name: fmt.Sprintf("%s%s", patchName, idxStr),
-				line: fmt.Sprintf("empty and ready for planting"),
+				line: "empty and ready for planting",
 			})
 			continue
 		}
@@ -582,7 +533,7 @@ func (g *Game) showFarmPatches(sess *net.Session, p *player.Player) []string {
 		if dead {
 			displays = append(displays, farmDisplay{
 				name: fmt.Sprintf("%s%s", patchName, idxStr),
-				line: fmt.Sprintf("contains a dead plant"),
+				line: "contains a dead plant",
 			})
 			continue
 		}
diff --git a/internal/game/act_gather.go b/internal/game/act_gather.go
index 0701fc4..447e23a 100644
--- a/internal/game/act_gather.go
+++ b/internal/game/act_gather.go
@@ -178,7 +178,7 @@ func (g *Game) advanceGather(sess *net.Session, p *player.Player) {
 				return
 			}
 		}
-		sess.WriteLine(fmt.Sprintf("%s", cfg.GatherMessage))
+		sess.WriteLine(cfg.GatherMessage)
 		d.Step = 1
 		p.Action.WaitLeft = engine.ToTicks(wait)
 		return
diff --git a/internal/game/act_room.go b/internal/game/act_room.go
index 889ce85..792d8bd 100644
--- a/internal/game/act_room.go
+++ b/internal/game/act_room.go
@@ -75,11 +75,3 @@ func (g *Game) BroadcastRespawns() {
 		}
 	}
 }
-
-// isCharLive reports whether the named player is currently connected via the
-// given session (used by older helpers that still reference it).
-func (g *Game) isCharLive(name string, sess *net.Session) bool {
-	g.charsMu.Lock()
-	defer g.charsMu.Unlock()
-	return g.loggedInChars[name] == sess
-}
diff --git a/internal/game/baseline_race_test.go b/internal/game/baseline_race_test.go
index de5b7b4..fc07c5e 100644
--- a/internal/game/baseline_race_test.go
+++ b/internal/game/baseline_race_test.go
@@ -6,7 +6,6 @@ package game
 // pass under -race with the single-owner design in place.
 
 import (
-	"fmt"
 	"sync"
 	"testing"
 	"thehouseoficarus/internal/net"
@@ -72,7 +71,7 @@ func TestBaselineRaceAdminRewriteWhilePlaying(t *testing.T) {
 	go func() {
 		defer wg.Done()
 		for i := 0; i < 200; i++ {
-			lines <- fmt.Sprintf("go north")
+			lines <- "go north"
 		}
 		close(lines)
 	}()
diff --git a/internal/game/cmd_drop.go b/internal/game/cmd_drop.go
index d77eb53..674f3da 100644
--- a/internal/game/cmd_drop.go
+++ b/internal/game/cmd_drop.go
@@ -229,7 +229,7 @@ func (g *Game) handleDropAll(sess *net.Session, input string) {
 	if len(dropped) == 0 {
 		sess.WriteLine("You have nothing to drop.")
 	} else {
-		sess.Write(fmt.Sprintf("You drop your "))
+		sess.Write("You drop your ")
 		formatPickupList(sess, dropped)
 	}
 	g.writePrompt(sess)
diff --git a/internal/game/cmd_estate_directory.go b/internal/game/cmd_estate_directory.go
index b28e634..2441157 100644
--- a/internal/game/cmd_estate_directory.go
+++ b/internal/game/cmd_estate_directory.go
@@ -49,7 +49,7 @@ func (g *Game) lookEstateDirectory(sess *net.Session) {
 	homeowners := g.scanHomeowners("owns_house_local_neighborhood")
 	sess.WriteLine("")
 	sess.WriteLine(g.colorize(sess, "dialog", "Estate Directory"))
-	sess.WriteLine(fmt.Sprintf("  A holographic terminal displaying property records for the Local Neighborhood."))
+	sess.WriteLine("  A holographic terminal displaying property records for the Local Neighborhood.")
 	sess.WriteLine("")
 	if len(homeowners) == 0 {
 		sess.WriteLine("  No registered homeowners in this area.")
diff --git a/internal/game/cmd_farm.go b/internal/game/cmd_farm.go
index 19cdf12..aaa3779 100644
--- a/internal/game/cmd_farm.go
+++ b/internal/game/cmd_farm.go
@@ -373,76 +373,6 @@ func (g *Game) doCure(sess *net.Session, input string) {
 	g.AccountStore.SaveCharacter(p)
 }
 
-func (g *Game) doInspect(sess *net.Session, input string) {
-	p := sess.Player
-
-	objInstances := g.World.AllObjInstances(p.RoomID)
-	var farmPatches []struct {
-		prefix string
-		defID  string
-		index  int
-	}
-
-	for _, obj := range objInstances {
-		if !farmPatchDefIDs[obj.DefID] {
-			continue
-		}
-		pref := farmFlagPrefix(obj.DefID, obj.Index)
-		if pref == "" {
-			continue
-		}
-		farmPatches = append(farmPatches, struct {
-			prefix string
-			defID  string
-			index  int
-		}{pref, obj.DefID, obj.Index})
-	}
-
-	if len(farmPatches) == 0 {
-		sess.WriteLine("There are no farming patches here.")
-		return
-	}
-
-	if input != "" {
-		lower := strings.ToLower(input)
-		var filtered []struct {
-			prefix string
-			defID  string
-			index  int
-		}
-		for _, fp := range farmPatches {
-			def, _ := g.ObjectStore.Load(fp.defID)
-			if def != nil && strings.Contains(strings.ToLower(def.Name), lower) {
-				filtered = append(filtered, fp)
-			}
-		}
-		if len(filtered) == 0 {
-			for _, fp := range farmPatches {
-				if strings.Contains(fp.prefix, lower) || strings.Contains(strings.ToLower(fp.defID), lower) {
-					filtered = append(filtered, fp)
-				}
-			}
-		}
-		farmPatches = filtered
-	}
-
-	for _, fp := range farmPatches {
-		g.ensureFarmState(p, fp.prefix)
-		def, _ := g.ObjectStore.Load(fp.defID)
-		patchName := fp.defID
-		if def != nil {
-			patchName = def.Name
-		}
-		indexStr := ""
-		if len(farmPatches) > 1 || fp.index > 0 {
-			indexStr = fmt.Sprintf(" %d", fp.index+1)
-		}
-
-		sess.WriteLine(fmt.Sprintf("=== %s%s ===", patchName, indexStr))
-		g.ShowFarmPatchDetail(sess, p, fp.prefix, fp.defID, fp.index)
-	}
-}
-
 func (g *Game) ShowFarmPatchDetail(sess *net.Session, p *player.Player, prefix, defID string, index int) {
 	weeds, _ := p.Flags[prefix+"_weeds"].(bool)
 	if weeds {
@@ -465,7 +395,7 @@ func (g *Game) ShowFarmPatchDetail(sess *net.Session, p *player.Player, prefix,
 
 	dead, _ := p.Flags[prefix+"_dead"].(bool)
 	if dead {
-		sess.WriteLine(fmt.Sprintf("  Status: Dead"))
+		sess.WriteLine("  Status: Dead")
 		sess.WriteLine(fmt.Sprintf("  Planted: %s", seedName))
 		sess.WriteLine("  (Rake to clear)")
 		return
@@ -473,7 +403,7 @@ func (g *Game) ShowFarmPatchDetail(sess *net.Session, p *player.Player, prefix,
 
 	diseased, _ := p.Flags[prefix+"_diseased"].(bool)
 	if diseased {
-		sess.WriteLine(fmt.Sprintf("  Status: Diseased!"))
+		sess.WriteLine("  Status: Diseased!")
 		sess.WriteLine(fmt.Sprintf("  Planted: %s", seedName))
 		sess.WriteLine("  (Use plant cure to save it)")
 		return
@@ -481,7 +411,7 @@ func (g *Game) ShowFarmPatchDetail(sess *net.Session, p *player.Player, prefix,
 
 	ready, _ := p.Flags[prefix+"_ready"].(bool)
 	if ready {
-		sess.WriteLine(fmt.Sprintf("  Status: Ready to harvest!"))
+		sess.WriteLine("  Status: Ready to harvest!")
 		sess.WriteLine(fmt.Sprintf("  Planted: %s", seedName))
 		return
 	}
diff --git a/internal/game/cmd_queued.go b/internal/game/cmd_queued.go
index 549c5fb..7ac05a6 100644
--- a/internal/game/cmd_queued.go
+++ b/internal/game/cmd_queued.go
@@ -43,13 +43,13 @@ func (g *Game) doQueued(sess *net.Session) {
 		if activeCmd.Args != "" {
 			cmd += " " + activeCmd.Args
 		}
-		sess.WriteLine(fmt.Sprintf("  Queued active action (executes after free actions):"))
-		sess.WriteLine(fmt.Sprintf("    %s", cmd))
+		sess.WriteLine("  Queued active action (executes after free actions):")
+		sess.WriteLine("    " + cmd)
 	}
 
 	sess.WriteLine("")
-	sess.WriteLine(fmt.Sprintf("  All queued actions take effect on the next game tick (600ms)."))
-	sess.WriteLine(fmt.Sprintf("  Free actions stack. Only the most recent active action survives."))
+	sess.WriteLine("  All queued actions take effect on the next game tick (600ms).")
+	sess.WriteLine("  Free actions stack. Only the most recent active action survives.")
 
 	names, _ := g.queue.ActivePositions(p.Name)
 	sort.Strings(names)
diff --git a/internal/game/cmd_remove.go b/internal/game/cmd_remove.go
index 3a451af..38f17a3 100644
--- a/internal/game/cmd_remove.go
+++ b/internal/game/cmd_remove.go
@@ -38,7 +38,7 @@ func (g *Game) doRemove(sess *net.Session, input string) {
 		if !ok {
 			continue
 		}
-		if strings.ToLower(string(slot)) == strings.ToLower(itemName) {
+		if strings.EqualFold(string(slot), itemName) {
 			foundSlot = slot
 			foundItemID = itemID
 			break
diff --git a/internal/game/cmd_room_remove_test.go b/internal/game/cmd_room_remove_test.go
index cd9569d..97ab859 100644
--- a/internal/game/cmd_room_remove_test.go
+++ b/internal/game/cmd_room_remove_test.go
@@ -71,14 +71,6 @@ func assertOutContains(t *testing.T, sess *net.Session, sub string) {
 	}
 }
 
-func assertOutNotContains(t *testing.T, sess *net.Session, sub string) {
-	t.Helper()
-	out := sess.Conn.(*removeTestConn).output()
-	if strings.Contains(out, sub) {
-		t.Errorf("expected session output to NOT contain %q, got:\n%s", sub, out)
-	}
-}
-
 // reloadAfterCmd re-reads a room from disk after a command has mutated it.
 func reloadRoom(t *testing.T, g *Game, id int) *world.Room {
 	t.Helper()
diff --git a/internal/game/cmd_tech.go b/internal/game/cmd_tech.go
index 0a5580c..1431228 100644
--- a/internal/game/cmd_tech.go
+++ b/internal/game/cmd_tech.go
@@ -126,7 +126,7 @@ func (g *Game) doTechList(sess *net.Session) {
 
 	for _, tech := range AllTechs {
 		status := ""
-		nameStr := tech.Name
+		var nameStr string
 		if tech.Level <= techLevel {
 			if p.HasActiveTech(tech.ID) {
 				status = color.Render(mode, g.resolveConstant(sess, "tech_status_on"), "ON")
diff --git a/internal/game/cmd_undig.go b/internal/game/cmd_undig.go
index a41cb08..c24b299 100644
--- a/internal/game/cmd_undig.go
+++ b/internal/game/cmd_undig.go
@@ -110,7 +110,7 @@ func (g *Game) listUndigOrphans(sess *net.Session, targetID int) {
 
 	if len(orphans) > 0 {
 		sess.WriteLine(g.colorize(sess, "warning",
-			fmt.Sprintf("WARNING: The following rooms will become unreachable after deletion:")))
+			"WARNING: The following rooms will become unreachable after deletion:"))
 		for _, rid := range orphans {
 			room, err := g.World.LoadRoom(rid)
 			name := fmt.Sprintf("#%d", rid)
@@ -154,7 +154,7 @@ func (g *Game) handleUndigConfirm(sess *net.Session, input string) {
 
 func (g *Game) performUndig(sess *net.Session, p *player.Player, targetID int) {
 	targetRoom, err := g.World.LoadRoom(targetID)
-	roomName := fmt.Sprintf("#%d", targetID)
+	var roomName string
 	if err == nil {
 		roomName = fmt.Sprintf("#%d (%s)", targetID, targetRoom.Name)
 	} else {
@@ -234,7 +234,7 @@ func (g *Game) performUndig(sess *net.Session, p *player.Player, targetID int) {
 			if g.Hub != nil {
 				g.Hub.EnterRoom(other, p.RoomID)
 			}
-			other.WriteLine(fmt.Sprintf("The room around you dissolves. You find yourself elsewhere."))
+			other.WriteLine("The room around you dissolves. You find yourself elsewhere.")
 			g.doLook(other)
 		}
 	}
diff --git a/internal/game/cmd_use.go b/internal/game/cmd_use.go
index 975eddb..12dbc73 100644
--- a/internal/game/cmd_use.go
+++ b/internal/game/cmd_use.go
@@ -192,7 +192,7 @@ func (g *Game) doUseItemOnTarget(sess *net.Session, p *player.Player, itemAName,
 
 	itemAID := matchesA[0].ID
 
-	matchesB := g.findInventoryMatches(itemBName, p)
+	var matchesB []itemMatch
 
 	objInstances := g.World.FindObjInstances(p.RoomID, itemBName)
 	if len(objInstances) > 0 {
diff --git a/internal/game/cmd_walk.go b/internal/game/cmd_walk.go
index 80600af..101c0fe 100644
--- a/internal/game/cmd_walk.go
+++ b/internal/game/cmd_walk.go
@@ -53,7 +53,7 @@ func parseWalkDirections(input string) ([]string, error) {
 			num = 1
 		}
 		if i >= len(input) {
-			return nil, fmt.Errorf("Unexpected end of directions.")
+			return nil, fmt.Errorf("unexpected end of directions")
 		}
 		ch := input[i]
 		i++
@@ -88,7 +88,7 @@ func parseWalkDirections(input string) ([]string, error) {
 		case 'd':
 			dir = string(world.Down)
 		default:
-			return nil, fmt.Errorf("Unknown direction: %c", ch)
+			return nil, fmt.Errorf("unknown direction: %c", ch)
 		}
 		for j := 0; j < num; j++ {
 			dirs = append(dirs, dir)
diff --git a/internal/game/core_course.go b/internal/game/core_course.go
index 15bd47e..03b091e 100644
--- a/internal/game/core_course.go
+++ b/internal/game/core_course.go
@@ -143,11 +143,7 @@ func (cs *CourseStore) GetObstacle(roomID int) *ObstacleInfo {
 func resolvePhases(obs ObstacleDef) []PhaseInfo {
 	phases := make([]PhaseInfo, 0, len(obs.Phases))
 	for _, p := range obs.Phases {
-		phases = append(phases, PhaseInfo{
-			Message:   p.Message,
-			Delay:     p.Delay,
-			FailCheck: p.FailCheck,
-		})
+		phases = append(phases, PhaseInfo(p))
 	}
 	return phases
 }
diff --git a/internal/game/core_login_account.go b/internal/game/core_login_account.go
index 1acd1a6..4c05373 100644
--- a/internal/game/core_login_account.go
+++ b/internal/game/core_login_account.go
@@ -379,7 +379,7 @@ func (g *Game) handleRenameAccount(sess *net.Session, input string) {
 func (g *Game) handlePurgeAccount(sess *net.Session, input string) {
 	input = strings.TrimSpace(input)
 	expected := "PURGE " + sess.Account.Name
-	if strings.ToUpper(input) != strings.ToUpper(expected) {
+	if !strings.EqualFold(input, expected) {
 		sess.WriteLine("Purge cancelled.")
 		g.showMenu(sess)
 		return
diff --git a/internal/game/core_login_char.go b/internal/game/core_login_char.go
index 8388bfb..c21ea87 100644
--- a/internal/game/core_login_char.go
+++ b/internal/game/core_login_char.go
@@ -261,7 +261,7 @@ func (g *Game) handleDeleteChar(sess *net.Session, input string) {
 
 	input = strings.TrimSpace(input)
 	expected := "DELETE " + sess.PendingChar
-	if strings.ToUpper(input) != strings.ToUpper(expected) {
+	if !strings.EqualFold(input, expected) {
 		sess.WriteLine("Delete cancelled.")
 		sess.PendingChar = ""
 		g.showMenu(sess)
diff --git a/internal/game/harness_test.go b/internal/game/harness_test.go
index 7898af2..a368634 100644
--- a/internal/game/harness_test.go
+++ b/internal/game/harness_test.go
@@ -75,14 +75,6 @@ func (c *chanConn) Contains(substr string) bool {
 	return strings.Contains(string(c.Bytes()), substr)
 }
 
-// send queues an input line for ReadMessage. No-op after close.
-func (c *chanConn) send(line string) {
-	select {
-	case c.in <- line:
-	case <-c.closed:
-	}
-}
-
 // harness wires a real Game (temp data dir) to fake transports driven from
 // per-connection goroutines plus a competing tick goroutine, reproducing the
 // production entry-point concurrency: session input, disconnect callbacks, and
@@ -255,12 +247,3 @@ func (h *harness) goInput(sess *net.Session, workers int) chan<- string {
 	}
 	return lines
 }
-
-const workers = 1
-
-// sessionFor returns the registered session for a character name.
-func (h *harness) sessionFor(name string) *net.Session {
-	h.mu.Lock()
-	defer h.mu.Unlock()
-	return h.sessions[name]
-}
diff --git a/internal/game/owner.go b/internal/game/owner.go
index ce1f687..9c7be64 100644
--- a/internal/game/owner.go
+++ b/internal/game/owner.go
@@ -177,18 +177,6 @@ func (g *Game) RunAdminOnOwner(fn func()) bool {
 	return accepted
 }
 
-// tryRun executes fn on the owner if it is currently idle-draining; it is
-// not currently used for correctness paths but exists for future non-blocking
-// administrative reads. It returns false when the queue is full.
-func (g *Game) tryRun(fn func()) bool {
-	o := g.owner
-	if o == nil {
-		fn()
-		return true
-	}
-	return o.submit(fn)
-}
-
 // currentGoroutineID returns the calling goroutine's ID parsed from its
 // stack header ("goroutine 123 [running]:"), 0 when unparseable.
 func currentGoroutineID() uint64 {
diff --git a/internal/game/production_index.go b/internal/game/production_index.go
index 77fc08a..672dcae 100644
--- a/internal/game/production_index.go
+++ b/internal/game/production_index.go
@@ -153,15 +153,6 @@ func (idx *CraftIndex) FindByStationInput(stationDefID, itemID string) []*item.I
 	return results
 }
 
-func craftEntryFor(def *item.ItemDef, itemID string) int {
-	for _, craft := range def.Craft {
-		if ei := craftEntry(craft, itemID); ei >= 0 {
-			return ei
-		}
-	}
-	return -1
-}
-
 func craftEntry(craft item.CraftDef, itemID string) int {
 	for ei, e := range craft.Ingredients {
 		for _, id := range e.Items {
diff --git a/internal/game/render_help.go b/internal/game/render_help.go
index c7d0aa0..7886f48 100644
--- a/internal/game/render_help.go
+++ b/internal/game/render_help.go
@@ -224,13 +224,6 @@ func matchesHelpTopic(h HelpDef, topic string) bool {
 	return false
 }
 
-func firstLine(s string) string {
-	if idx := strings.Index(s, "\n"); idx >= 0 {
-		return s[:idx]
-	}
-	return s
-}
-
 func (g *Game) executeHelp(sess *net.Session, args []string, rawInput string) {
 	if len(args) == 0 {
 		g.doHelp(sess, "")
diff --git a/internal/game/sys_assassin.go b/internal/game/sys_assassin.go
index 65ddb7c..fc814ec 100644
--- a/internal/game/sys_assassin.go
+++ b/internal/game/sys_assassin.go
@@ -2,68 +2,12 @@ package game
 
 import (
 	"fmt"
-	"math/rand"
 
 	"thehouseoficarus/internal/net"
 	"thehouseoficarus/internal/player"
 	"thehouseoficarus/internal/world"
 )
 
-type assassinTaskEntry struct {
-	MobID    string
-	MinLevel int
-	MaxLevel int
-	MinCount int
-	MaxCount int
-	Weight   int
-}
-
-var assassinTaskTable = []assassinTaskEntry{
-	{"man", 1, 15, 10, 25, 8},
-	{"cow", 1, 15, 10, 25, 8},
-	{"slug", 1, 99, 15, 45, 15},
-	{"drone", 15, 99, 20, 50, 12},
-	{"crawler", 30, 99, 15, 40, 10},
-	{"phantom", 45, 99, 10, 30, 8},
-}
-
-func (g *Game) assignAssassinTask(sess *net.Session, p *player.Player) {
-	level := p.Level(player.Assassin)
-	var eligible []assassinTaskEntry
-	totalWeight := 0
-	for _, entry := range assassinTaskTable {
-		if level >= entry.MinLevel && level <= entry.MaxLevel {
-			eligible = append(eligible, entry)
-			totalWeight += entry.Weight
-		}
-	}
-	if len(eligible) == 0 {
-		sess.WriteLine("The Client shakes their head. \"Nothing available for your level.\"")
-		return
-	}
-	roll := rand.Intn(totalWeight)
-	var chosen assassinTaskEntry
-	for _, entry := range eligible {
-		roll -= entry.Weight
-		if roll < 0 {
-			chosen = entry
-			break
-		}
-	}
-	count := chosen.MinCount + rand.Intn(chosen.MaxCount-chosen.MinCount+1)
-	g.setPlayerFlag(p, "assassin_task_mob", chosen.MobID)
-	g.setPlayerFlag(p, "assassin_task_total", count)
-	g.setPlayerFlag(p, "assassin_task_remaining", count)
-	g.AccountStore.SaveCharacter(p)
-
-	def, err := g.MobStore.LoadDef(chosen.MobID)
-	name := chosen.MobID
-	if err == nil {
-		name = def.Name
-	}
-	sess.WriteLine(g.colorize(sess, "assassin_task", fmt.Sprintf("\"Your target: %d %ss. Get to work.\"", count, name)))
-}
-
 func (g *Game) onAssassinKill(sess *net.Session, p *player.Player, mob *world.MobInstance) {
 	taskMob := getPlayerFlagString(p, "assassin_task_mob")
 	if taskMob == "" || taskMob != mob.DefID {
@@ -93,7 +37,7 @@ func (g *Game) onAssassinKill(sess *net.Session, p *player.Player, mob *world.Mo
 		rep += bonus
 		currentRep := getPlayerFlagInt(p, "assassin_reputation")
 		g.setPlayerFlag(p, "assassin_reputation", currentRep+rep)
-		sess.WriteLine(g.colorize(sess, "assassin_task", fmt.Sprintf("*** Assassin task complete! ***")))
+		sess.WriteLine(g.colorize(sess, "assassin_task", "*** Assassin task complete! ***"))
 		if bonus > 0 {
 			sess.WriteLine(g.colorize(sess, "assassin_task", fmt.Sprintf("  Streak bonus! %d tasks in a row. +%d bonus reputation.", streak, bonus)))
 		}
@@ -110,50 +54,6 @@ func (g *Game) onAssassinKill(sess *net.Session, p *player.Player, mob *world.Mo
 	g.AccountStore.SaveCharacter(p)
 }
 
-func (g *Game) skipAssassinTask(sess *net.Session, p *player.Player) {
-	rep := getPlayerFlagInt(p, "assassin_reputation")
-	if rep < 30 {
-		sess.WriteLine("You don't have enough Reputation to skip. (Need 30, have " + fmt.Sprint(rep) + ")")
-		return
-	}
-	g.setPlayerFlag(p, "assassin_reputation", rep-30)
-	delete(p.Flags, "assassin_task_mob")
-	g.setPlayerFlag(p, "assassin_task_remaining", 0)
-	g.setPlayerFlag(p, "assassin_task_total", 0)
-	g.setPlayerFlag(p, "assassin_streak", 0)
-	g.AccountStore.SaveCharacter(p)
-}
-
-func (g *Game) extendAssassinTask(sess *net.Session, p *player.Player) {
-	rep := getPlayerFlagInt(p, "assassin_reputation")
-	if rep < 30 {
-		sess.WriteLine("You don't have enough Reputation to extend. (Need 30, have " + fmt.Sprint(rep) + ")")
-		return
-	}
-	taskMob := getPlayerFlagString(p, "assassin_task_mob")
-	if taskMob == "" {
-		sess.WriteLine("You don't have an active task to extend.")
-		return
-	}
-	g.setPlayerFlag(p, "assassin_reputation", rep-30)
-	total := getPlayerFlagInt(p, "assassin_task_total")
-	remaining := getPlayerFlagInt(p, "assassin_task_remaining")
-	extension := total / 2
-	if extension < 5 {
-		extension = 5
-	}
-	g.setPlayerFlag(p, "assassin_task_total", total+extension)
-	g.setPlayerFlag(p, "assassin_task_remaining", remaining+extension)
-	g.AccountStore.SaveCharacter(p)
-
-	def, _ := g.MobStore.LoadDef(taskMob)
-	name := taskMob
-	if def != nil {
-		name = def.Name
-	}
-	sess.WriteLine(fmt.Sprintf("Task extended by %d. Kill %d more %ss (%d total).", extension, remaining+extension, name, total+extension))
-}
-
 func streakBonus(streak int) int {
 	if streak%1000 == 0 {
 		return 50
diff --git a/internal/game/sys_buff.go b/internal/game/sys_buff.go
index 3b8555c..01660d8 100644
--- a/internal/game/sys_buff.go
+++ b/internal/game/sys_buff.go
@@ -3,7 +3,6 @@ package game
 import (
 	"strings"
 
-	"thehouseoficarus/internal/net"
 	"thehouseoficarus/internal/player"
 )
 
@@ -49,7 +48,3 @@ func (g *Game) buffLevelBonus(p *player.Player, stat string) int {
 	baseLevel := p.Level(player.SkillName(strings.ToLower(stat)))
 	return baseLevel * totalPercent / 100
 }
-
-func (g *Game) totalBuffedLevel(sess *net.Session, p *player.Player, stat string) int {
-	return p.Level(player.SkillName(strings.ToLower(stat))) + g.buffLevelBonus(p, stat)
-}
diff --git a/internal/player/validate.go b/internal/player/validate.go
index 1a2a5b9..015b3d8 100644
--- a/internal/player/validate.go
+++ b/internal/player/validate.go
@@ -17,7 +17,7 @@ func ValidName(name string) error {
 
 func ValidPassword(pw string) error {
 	if len(pw) > 128 {
-		return fmt.Errorf("Password too long.")
+		return fmt.Errorf("password too long")
 	}
 	return nil
 }
diff --git a/internal/validate/checks.go b/internal/validate/checks.go
index 344df3a..6994654 100644
--- a/internal/validate/checks.go
+++ b/internal/validate/checks.go
@@ -782,51 +782,51 @@ func validateDropTables(s Source) []Issue {
 
 			if d.ItemID != "" && d.Table != "" {
 				issues = append(issues, Issue{
-					Level: "WARN",
-					Type:  "integrity",
+					Level:   "WARN",
+					Type:    "integrity",
 					Message: fmt.Sprintf("Drop table %q entry %d: both item_id and table set (only one is used per entry)", id, i+1),
 				})
 			}
 			if d.ItemID == "" && d.Table == "" {
 				issues = append(issues, Issue{
-					Level: "WARN",
-					Type:  "integrity",
+					Level:   "WARN",
+					Type:    "integrity",
 					Message: fmt.Sprintf("Drop table %q entry %d: neither item_id nor table set (roll produces nothing)", id, i+1),
 				})
 			}
 
 			if d.Depletes {
 				issues = append(issues, Issue{
-					Level: "WARN",
-					Type:  "integrity",
+					Level:   "WARN",
+					Type:    "integrity",
 					Message: fmt.Sprintf("Drop table %q entry %d: 'depletes' is ignored on shared drop table entries; set it on the gather entry that references this table instead", id, i+1),
 				})
 			}
 			if d.Level > 0 {
 				issues = append(issues, Issue{
-					Level: "WARN",
-					Type:  "integrity",
+					Level:   "WARN",
+					Type:    "integrity",
 					Message: fmt.Sprintf("Drop table %q entry %d: 'level' is ignored on shared drop table entries; set it on the gather entry that references this table", id, i+1),
 				})
 			}
 			if d.XP > 0 {
 				issues = append(issues, Issue{
-					Level: "WARN",
-					Type:  "integrity",
+					Level:   "WARN",
+					Type:    "integrity",
 					Message: fmt.Sprintf("Drop table %q entry %d: 'xp' is ignored on shared drop table entries; set it on the gather entry that references this table", id, i+1),
 				})
 			}
 			if d.Tool != "" {
 				issues = append(issues, Issue{
-					Level: "WARN",
-					Type:  "integrity",
+					Level:   "WARN",
+					Type:    "integrity",
 					Message: fmt.Sprintf("Drop table %q entry %d: 'tool' is ignored on shared drop table entries; set it on the gather entry that references this table", id, i+1),
 				})
 			}
 			if d.SuccessMessage != "" {
 				issues = append(issues, Issue{
-					Level: "WARN",
-					Type:  "integrity",
+					Level:   "WARN",
+					Type:    "integrity",
 					Message: fmt.Sprintf("Drop table %q entry %d: 'success_message' is ignored on shared drop table entries; set it on the gather entry that references this table", id, i+1),
 				})
 			}