refactor: simplifcation, change how rooms are stored in player yaml, remove legacy code

3 files changed, 191 insertions, 182 deletions

diff --git a/building_guide/behaviors.md b/building_guide/behaviors.md
index 3063677..26c12ec 100644
--- a/building_guide/behaviors.md
+++ b/building_guide/behaviors.md
@@ -479,10 +479,10 @@ talk:
 ### Interaction Reference
 
 The unified **Trigger** shape is the shared wrapper used by every event block: `on_use`,
-`on_look`, `on_kill`, `on_traverse`, `on_enter`, `on_exit`, `on_flag_change`,
-`on_global_flag_change`, and global trigger files (`data/triggers/*.yaml`). When a block's
-list of Triggers is evaluated, the first whose filters pass fires and its `steps` run as a
-scripted sequence (first-match-wins).
+`on_look`, `on_kill`, `on_traverse`, `on_enter`, `on_exit`, and flag-trigger files under
+`data/triggers/player_flag/` or `data/triggers/global_flag/` (`on_player_flag` /
+`on_global_flag`). When a block's list of Triggers is evaluated, the first whose filters
+pass fires and its `steps` run as a scripted sequence (first-match-wins).
 
 | Field | Scope | Description |
 |-------|-------|-------------|
@@ -490,8 +490,8 @@ scripted sequence (first-match-wins).
 | `item_id` | on_use/on_look/on_kill | `on_use`: required item (`use <item> on <obj>`); empty = bare `use <obj>`. `on_look`: only fires if carrying this item. `on_kill`: only fires if wielding this weapon. |
 | `condition` | all | Optional Trigger-level gate (Condition struct). |
 | `steps` | all | Ordered list of Step entries run as a scripted sequence. |
-| `on_player_flag` | on_flag_change only | Player flag this trigger watches. |
-| `on_global_flag` | on_global_flag_change only | Global flag this trigger watches. |
+| `on_player_flag` | flag-trigger files only | Player flag this trigger watches. |
+| `on_global_flag` | flag-trigger files only | Global flag this trigger watches. |
 | `value` | flag triggers | Optional value-match filter. |
 
 Talk node/option actions still use the NodeAction shape (`action:` with the effect fields
diff --git a/building_guide/rooms.md b/building_guide/rooms.md
index 719c09e..25c6f5f 100644
--- a/building_guide/rooms.md
+++ b/building_guide/rooms.md
@@ -355,14 +355,15 @@ validation reports invalid definitions, and game lookup refuses invalid room
 casino configurations. Raw file editing is not a validated save endpoint.
 
 - IDs must be nonempty, have no surrounding whitespace, and be unique across
-  the room's tables and machines (including legacy slots table entries).
-- Supported table games are `blackjack` and `baccarat`; machines use `slots`
+  the room's tables and machines.
+- Supported table games are `blackjack` and `baccarat`; slots are machines only
+  and must be declared under `casino_machines`. A `slots` entry under
+  `casino_tables` is rejected. Machines use `slots`
   with the optional variant `huff_and_even_more_puff`. A machine variant is
   registered in Go (`slotVariants` in `internal/casino/registry.go`); naming an
   unregistered variant is a validation error.
 - A multiplayer table is addressed by its game name (`play blackjack`), so a
-  room may host only one table per game; a legacy slots table still collides
-  with a slots machine.
+  room may host only one table per game.
 - A machine is addressed by its `variant` when one is declared, so a room may
   host several variants of one game, each reached by its own variant name. A
   bare game name addresses a machine only when it is the sole machine of that
@@ -607,31 +608,33 @@ mobs:
 
 ---
 
-### Room flag triggers
+### Flag triggers
 
-A room that needs to react when a flag changes uses the `on_flag_change:` / `on_global_flag_change:`
-blocks (these replace the old `triggers:` block). Each entry watches one flag, runs a `steps`
-sequence when that flag changes, and resolves broadcasts/spawns against the room. See
+A trigger that reacts to a flag change is a **file-backed trigger**, not a room field. Put it
+under `data/triggers/player_flag/` (watch a player flag with `on_player_flag:`) or
+`data/triggers/global_flag/` (watch a global flag with `on_global_flag:`). Each file holds one
+trigger, the filename stem is its id, and the trigger must set exactly one of those two keys —
+a file with neither is a startup ERROR because it is loaded but can never fire. See
 `triggers.md` for the full reference.
 
 ```yaml
-on_flag_change:
-  - on_player_flag: lever_pulled
-    condition:
-      room: 1001                   # opt-in: only fires if the player is in this room
-    steps:
-      - wait: 5
-        messages: ["The cabin shakes as the small craft touches down"]
-      - wait: 5
-        messages: ["The pistons hiss as the rear staircase opens"]
-      - set_player_flags:
-          1001_touchdown: true
-```
-
-Flag triggers listen **globally** — they fire regardless of where the flag is set. The old
-room `triggers:` block was implicitly room-scoped; migration injects `condition: { room:
-<id> }` to preserve that. Delete the `room` condition to make the trigger fire wherever the
-player is. For server-wide events use global trigger files in `data/triggers/` instead.
+# data/triggers/player_flag/1001_touchdown.yaml
+on_player_flag: lever_pulled
+condition:
+  room: 1001                   # opt-in: only fires if the player is in this room
+steps:
+  - wait: 5
+    messages: ["The cabin shakes as the small craft touches down"]
+  - wait: 5
+    messages: ["The pistons hiss as the rear staircase opens"]
+  - set_player_flags:
+      1001_touchdown: true
+```
+
+Flag triggers listen **globally** — they fire regardless of where the flag is set. Add
+`condition: { room: <id> }` to scope one to the room it belongs to; delete that condition to
+let it fire wherever the player is. Room files support only `on_enter`, `on_exit`, and exit
+`on_traverse` trigger blocks; there is no room-level `on_flag_change:` field.
 
 ---
 
diff --git a/building_guide/triggers.md b/building_guide/triggers.md
index c32830d..ba44c40 100644
--- a/building_guide/triggers.md
+++ b/building_guide/triggers.md
@@ -181,8 +181,8 @@ entity:
 | Object | `on_use`, `on_look` |
 | Mob | `on_kill` |
 | Exit (room YAML) | `on_traverse` |
-| Room | `on_enter`, `on_exit` (NEW), `on_flag_change`, `on_global_flag_change` |
-| Global file (`data/triggers/*.yaml`) | one Trigger per file (flag triggers) |
+| Room | `on_enter`, `on_exit` (NEW) |
+| Flag trigger file (`data/triggers/player_flag/`, `data/triggers/global_flag/`) | one Trigger per file (`on_player_flag` / `on_global_flag`) |
 
 - **on_use / on_look** — see `objects.md`. `item_id` filters which item triggers the entry.
 - **on_kill** — see `mobs.md`. `item_id` filters by wielded weapon.
@@ -193,8 +193,7 @@ entity:
 - **on_exit** (NEW) — fires when a player leaves the room, **before** `RoomID` is updated
   to the destination. Broadcasts/spawn resolve against the old (departed) room. Mirror of
   on_enter, useful for parting messages, closing spawns, or recording departures.
-- **on_flag_change** / **on_global_flag_change** — flag-watch triggers, replacing the old
-  room `triggers:` block. See Flag triggers below.
+- **on_flag_change** / **on_global_flag_change** — flag-watch triggers are **file-backed**, one per file under `data/triggers/player_flag/` or `data/triggers/global_flag/`. They are not room fields. See Flag triggers below.
 
 ### Quick Start: Landing Sequence
 
@@ -259,91 +258,99 @@ triggers watching that flag.
 
 ### Flag triggers
 
-`on_flag_change` and `on_global_flag_change` replace the old room `triggers:` block. Each
-entry carries the flag it watches (`on_player_flag` or `on_global_flag`), an optional
-`condition` (use `player_flag`/`global_flag` + `value` to match a specific flag value), and
-a `steps` list.
+A flag trigger is a **standalone trigger file**, one per flag, under
+`data/triggers/player_flag/` (set `on_player_flag:`) or `data/triggers/global_flag/` (set
+`on_global_flag:`). The filename stem is the trigger id. Each file carries the flag it
+watches, an optional `condition` (use `player_flag`/`global_flag` + `value` to match a
+specific flag value), and a `steps` list. The block sits at the top level of the file —
+there is no `on_flag_change:` wrapper and no room-file form.
 
 Key behaviors:
 
 - **Listen globally.** A flag-change trigger fires regardless of where the flag is set.
-  The event block lives in a room (for broadcasts/spawns to use that room) or in a global
-  file (see Global trigger files).
+  Add `condition: { room: <id> }` when a broadcast/spawn should resolve against a specific
+  room, or use a global trigger file for server-wide events (see Global trigger files).
 - **Room scoping is opt-in.** Use `condition: { room: <id> }` to restrict the trigger to
-  players currently in that room. Migration injects `{ room: <roomID> }` into migrated
-  room triggers to preserve the old room-scoped behavior; authors can delete it to make the
-  trigger fire globally.
+  players currently in that room.
 - **Fires on the non-existent → existent transition.** Setting a flag that didn't exist
   before counts as a change and fires the trigger. Setting a flag to the same value it
   already has does **not** re-fire.
 - **Triggers activate on becoming truthy.** Setting `true → false` does **not** fire.
 
 ```yaml
-# A room watches a player flag and plays a sequence for that player
-on_flag_change:
-  - on_player_flag: lever_pulled
-    steps:
-      - broadcast: "The lever snaps back into place with a loud clunk."
-      - set_player_flags:
-          lever_pulled: false      # reset so next pull re-fires
+# data/triggers/player_flag/lever_pulled.yaml
+on_player_flag: lever_pulled
+steps:
+  - broadcast: "The lever snaps back into place with a loud clunk."
+  - set_player_flags:
+      lever_pulled: false      # reset so next pull re-fires
 ```
 
-To migrate the old room `triggers:` block, replace `triggers:` with `on_flag_change:` (for
-`on_player_flag`) or `on_global_flag_change:` (for `on_global_flag`) and add
-`condition: { room: <id> }` if you want the old room-scoped behavior.
+A trigger file that sets neither `on_player_flag` nor `on_global_flag` is a startup ERROR:
+it is loaded but indexed nowhere and can never fire.
 
 ### Value-matching flag triggers
 
 By default a flag trigger fires when the watched flag becomes truthy. Use a `condition` with
 a `player_flag`/`global_flag` + `value` to require a specific value — enabling multi-stage
-quests off one numeric flag:
+quests off one numeric flag. Because each file watches exactly one flag, a multi-stage flag
+uses one file per stage:
 
 ```yaml
-on_flag_change:
-  - on_player_flag: quest_stage
-    condition:
-      player_flag: quest_stage
-      value: 1
-    steps:
-      - messages: ["Quest started — find the crystal shard."]
-  - on_player_flag: quest_stage
-    condition:
-      player_flag: quest_stage
-      value: 2
-    steps:
-      - messages: ["You found the shard — return to the elder."]
-  - on_player_flag: quest_stage
-    condition:
-      player_flag: quest_stage
-      value: 3
-    steps:
-      - messages: ["The ritual begins..."]
-      - wait: 10
-        broadcast: "The temple hums with ancient power!"
-      - spawn_mob: crystal_guardian
+# data/triggers/player_flag/quest_stage_1.yaml
+on_player_flag: quest_stage
+condition:
+  player_flag: quest_stage
+  value: 1
+steps:
+  - messages: ["Quest started — find the crystal shard."]
+```
+
+```yaml
+# data/triggers/player_flag/quest_stage_2.yaml
+on_player_flag: quest_stage
+condition:
+  player_flag: quest_stage
+  value: 2
+steps:
+  - messages: ["You found the shard — return to the elder."]
+```
+
+```yaml
+# data/triggers/global_flag/ritual.yaml
+on_global_flag: ritual_stage
+condition:
+  global_flag: ritual_stage
+  value: 3
+steps:
+  - messages: ["The ritual begins..."]
+  - wait: 10
+    broadcast: "The temple hums with ancient power!"
+  - spawn_mob: crystal_guardian
 ```
 
 ### Global flag trigger
 
-A room can watch a global flag and fire once globally (not per-player). Everyone in the
-room sees the broadcast:
+A global-flag trigger file fires once globally (not per-player), and its broadcast is seen
+by every connected player. (`broadcast` inside a player-flag trigger is seen by that player.)
 
 ```yaml
-on_global_flag_change:
-  - on_global_flag: floodgate_open
-    steps:
-      - broadcast: "Ancient gears grind as the floodgate slowly opens..."
-      - wait: 15
-        broadcast: "Water thunders through the opening!"
-      - set_global_flags:
-          valley_flooded: true
+# data/triggers/global_flag/floodgate.yaml
+on_global_flag: floodgate_open
+steps:
+  - broadcast: "Ancient gears grind as the floodgate slowly opens..."
+  - wait: 15
+    broadcast: "Water thunders through the opening!"
+  - set_global_flags:
+      valley_flooded: true
 ```
 
 ### Global trigger files
 
-Global triggers live one-per-file in `data/triggers/`. They fire regardless of where the
-flag-setting player is. Use them for server-wide events. The filename stem is the trigger
-ID (must be globally unique). One Trigger per file — the block fields sit at the top level:
+Global triggers live one-per-file in `data/triggers/player_flag/` or
+`data/triggers/global_flag/`. They fire regardless of where the flag-setting player is. Use
+them for server-wide events. The filename stem is the trigger ID (must be globally unique).
+One Trigger per file — the block fields sit at the top level:
 
 ```yaml
 # data/triggers/announce_99.yaml
@@ -374,24 +381,23 @@ steps:
 
 ### Boss arena — puzzle unlocks a boss
 
-Player activates an altar (on a separate object) setting a player flag, and this room's
-`on_flag_change` triggers the boss spawn:
+Player activates an altar (on a separate object) setting a player flag, and a flag trigger
+file spawns the boss:
 
 ```yaml
-# data/rooms/dungeon/9001.yaml
-on_flag_change:
-  - on_player_flag: activated_altar
-    steps:
-      - broadcast: "The altar glows with an eerie light..."
-      - wait: 10
-        broadcast: "The ground trembles beneath your feet."
-      - wait: 20
-        broadcast: "A massive guardian emerges from the shadows!"
-      - spawn_mob:
-          id: altar_guardian
-          owner_only: true
-          despawn_on_leave: true
-          despawn_rooms: [450, 451, 452]
+# data/triggers/player_flag/activated_altar.yaml
+on_player_flag: activated_altar
+steps:
+  - broadcast: "The altar glows with an eerie light..."
+  - wait: 10
+    broadcast: "The ground trembles beneath your feet."
+  - wait: 20
+    broadcast: "A massive guardian emerges from the shadows!"
+  - spawn_mob:
+      id: altar_guardian
+      owner_only: true
+      despawn_on_leave: true
+      despawn_rooms: [450, 451, 452]
 ```
 
 The boss is `owner_only` — only the player who triggered it can interact with it. It
@@ -400,23 +406,23 @@ When the owner leaves those rooms, the boss begins despawning.
 
 ### Story beat — timed cutscene after NPC conversation
 
-An NPC conversation node sets `quest_ritual: started`. A room trigger plays a dramatic
-sequence for that player:
+An NPC conversation node sets `quest_ritual: started`. A flag trigger file plays a
+dramatic sequence for that player:
 
 ```yaml
-on_flag_change:
-  - on_player_flag: quest_ritual
-    steps:
-      - wait: 8
-        messages: ["The elder begins to chant in a language you don't recognize."]
-      - wait: 6
-        messages: ["Wisps of light swirl around the altar."]
-      - wait: 4
-        messages: ["The ground beneath you shudders as the ritual reaches its peak."]
-      - wait: 6
-        broadcast: "A blinding flash fills the chamber!"
-      - teleport: 601
-        messages: ["You open your eyes. You're somewhere else entirely."]
+# data/triggers/player_flag/quest_ritual.yaml
+on_player_flag: quest_ritual
+steps:
+  - wait: 8
+    messages: ["The elder begins to chant in a language you don't recognize."]
+  - wait: 6
+    messages: ["Wisps of light swirl around the altar."]
+  - wait: 4
+    messages: ["The ground beneath you shudders as the ritual reaches its peak."]
+  - wait: 6
+    broadcast: "A blinding flash fills the chamber!"
+  - teleport: 601
+    messages: ["You open your eyes. You're somewhere else entirely."]
 ```
 
 The final step uses `teleport` and `messages` (the triggering player is moved and sees a
@@ -430,19 +436,22 @@ When a step sets a flag, any triggers watching that flag fire immediately (on th
 tick). This lets you chain sequences:
 
 ```yaml
-on_flag_change:
-  - on_player_flag: phase_1_done
-    steps:
-      - broadcast: "The first seal cracks."
-      - set_player_flags:
-          phase_2_started: true       # triggers the next trigger
+# data/triggers/player_flag/phase_1_done.yaml
+on_player_flag: phase_1_done
+steps:
+  - broadcast: "The first seal cracks."
+  - set_player_flags:
+      phase_2_started: true       # triggers the next trigger
+```
 
-  - on_player_flag: phase_2_started
-    steps:
-      - wait: 10
-        broadcast: "The second seal glows brighter..."
-      - wait: 10
-        spawn_mob: phase_2_adds
+```yaml
+# data/triggers/player_flag/phase_2_started.yaml
+on_player_flag: phase_2_started
+steps:
+  - wait: 10
+    broadcast: "The second seal glows brighter..."
+  - wait: 10
+    spawn_mob: phase_2_adds
 ```
 
 Both sequences run concurrently — phase 2's wait countdown starts on the same tick phase
@@ -506,13 +515,13 @@ spawn_mob:
 Use `despawn_mob` in a step to remove previously spawned mobs:
 
 ```yaml
-on_flag_change:
-  - on_player_flag: puzzle_solved
-    steps:
-      - despawn_mob: puzzle_guardian       # remove the puzzle mob
-      - wait: 10
-        broadcast: "The guardian dissolves into mist."
-      - spawn_mob: boss_guardian           # spawn the real boss
+# data/triggers/player_flag/puzzle_solved.yaml
+on_player_flag: puzzle_solved
+steps:
+  - despawn_mob: puzzle_guardian       # remove the puzzle mob
+  - wait: 10
+    broadcast: "The guardian dissolves into mist."
+  - spawn_mob: boss_guardian           # spawn the real boss
 ```
 
 `despawn_mob` with an owner only removes mobs spawned by that player. Without an owner (in
@@ -613,59 +622,56 @@ on_look:
 **Step 2: Blood trail in room 5002** — flag trigger fires on value 1
 
 ```yaml
-# data/rooms/city/5002.yaml
-on_flag_change:
-  - on_player_flag: investigation
-    condition:
-      all_of:
-        - player_flag: investigation
-          value: 1
-        - room: 5002
-    steps:
-      - wait: 3
-        messages: ["You notice a trail of blood leading east..."]
-      - set_player_flags:
-          investigation: 2
+# data/triggers/player_flag/investigation_1.yaml
+on_player_flag: investigation
+condition:
+  all_of:
+    - player_flag: investigation
+      value: 1
+    - room: 5002
+steps:
+  - wait: 3
+    messages: ["You notice a trail of blood leading east..."]
+  - set_player_flags:
+      investigation: 2
 ```
 
 **Step 3: Broken dagger in room 5003** — flag trigger fires on value 2
 
 ```yaml
-# data/rooms/city/5003.yaml
-on_flag_change:
-  - on_player_flag: investigation
-    condition:
-      all_of:
-        - player_flag: investigation
-          value: 2
-        - room: 5003
-    steps:
-      - wait: 3
-        messages: ["A glint of metal catches your eye under a crate."]
+# data/triggers/player_flag/investigation_2.yaml
+on_player_flag: investigation
+condition:
+  all_of:
+    - player_flag: investigation
+      value: 2
+    - room: 5003
+steps:
+  - wait: 3
+    messages: ["A glint of metal catches your eye under a crate."]
 ```
 
 **Step 4: Confrontation** — flag trigger fires on value 3 (set by a separate talk node),
 spawns boss
 
 ```yaml
-# data/rooms/city/5004.yaml
-on_flag_change:
-  - on_player_flag: investigation
-    condition:
-      all_of:
-        - player_flag: investigation
-          value: 3
-        - room: 5004
-    steps:
-      - wait: 5
-        broadcast: "A shadow detaches itself from the warehouse wall..."
-      - wait: 5
-        broadcast: "The assassin steps into the light, blade drawn."
-      - spawn_mob:
-          id: assassin_boss
-          owner_only: true
-          despawn_on_leave: true
-          despawn_rooms: [5004]
+# data/triggers/player_flag/investigation_3.yaml
+on_player_flag: investigation
+condition:
+  all_of:
+    - player_flag: investigation
+      value: 3
+    - room: 5004
+steps:
+  - wait: 5
+    broadcast: "A shadow detaches itself from the warehouse wall..."
+  - wait: 5
+    broadcast: "The assassin steps into the light, blade drawn."
+  - spawn_mob:
+      id: assassin_boss
+      owner_only: true
+      despawn_on_leave: true
+      despawn_rooms: [5004]
 ```
 
 The player must stay in room 5004 to fight the boss. If they flee, the boss despawns and