drain object queues after each object

kiln-core/CLAUDE.md

@@ -34,7 +34,7 @@ The core types that were formerly monolithic in `game.rs` are now split into foc
 - `PortalDef { x, y, target_map, target_entry }` — parsed from map files, not yet runtime-wired.
 
 **`kiln-core/src/object_def.rs`** — scripted objects (`pub(crate)`):
-- `ObjectDef` — a scripted tile: `id: ObjectId` (its stable id, assigned when the object is added to a board), `x`, `y`, `z: usize` (layer index, drives draw order), `glyph: Glyph`, `queue: ObjQueue` (its private output queue of pending [`Action`]s, drained onto the board queue between script calls — see `api::queue`), `solid: bool` (default `true`), `opaque: bool` (default `true`), `pushable: bool` (default `false`), `grab: bool` (default `false`; set when a grab archetype like a gem is expanded — walking onto it fires `grab()`), `script_name: Option<String>`, `builtin_script: Option<&'static str>` (embedded source set when a script-backed archetype like a pusher is expanded at load; the expansion also sets `script_name` to a synthetic `BUILTIN_*` compile-key, so `builtin_script` supplies the *source* while `script_name` is the *key*; not serialized — see [`builtin_scripts`]), `tags: HashSet<String>`, `name: Option<String>`. The optional `name` is validated for board-wide uniqueness at load time; the first claimant keeps the name and any later duplicate has its name cleared to `None` (nonfatal). `ObjectDef::new(x, y)` constructs with defaults (`z = 0`). `ObjectDef::default_glyph()` returns tile 63 (`?`) yellow on black.
+- `ObjectDef` — a scripted tile: `id: ObjectId` (its stable id, assigned when the object is added to a board), `x`, `y`, `z: usize` (layer index, drives draw order), `glyph: Glyph`, `queue: ObjQueue` (its private output queue of pending [`Action`]s, drained into a batch of actions that `GameState` applies immediately after the object's hook — see `api::queue`), `solid: bool` (default `true`), `opaque: bool` (default `true`), `pushable: bool` (default `false`), `grab: bool` (default `false`; set when a grab archetype like a gem is expanded — walking onto it fires `grab()`), `script_name: Option<String>`, `builtin_script: Option<&'static str>` (embedded source set when a script-backed archetype like a pusher is expanded at load; the expansion also sets `script_name` to a synthetic `BUILTIN_*` compile-key, so `builtin_script` supplies the *source* while `script_name` is the *key*; not serialized — see [`builtin_scripts`]), `tags: HashSet<String>`, `name: Option<String>`. The optional `name` is validated for board-wide uniqueness at load time; the first claimant keeps the name and any later duplicate has its name cleared to `None` (nonfatal). `ObjectDef::new(x, y)` constructs with defaults (`z = 0`). `ObjectDef::default_glyph()` returns tile 63 (`?`) yellow on black.
 
 **`kiln-core/src/layer.rs`** — palette layers (the map-file/draw-stack unit):
 - `Layer { cells: Vec<(Glyph, Archetype)> }` (`pub(crate)`) — one row-major draw layer. A cell whose `glyph.tile == 0` (`Glyph::transparent()`) draws nothing, so the layer beneath shows through; solidity comes from the archetype, independent of transparency.
@@ -71,14 +71,14 @@ The core types that were formerly monolithic in `game.rs` are now split into foc
 - `SpeechBubble { object_id, text, remaining }` — an active speech bubble created by a script's `say(s)` call. `remaining` counts down in `GameState::tick`; when it reaches zero the bubble is removed. At most one bubble per object (a new `say()` replaces the old one).
 - `SAY_DURATION: f64` — how long a bubble lives (3.0 seconds).
 - `Scroll { source: ObjectId, lines: Vec<ScrollLine> }` — an active scroll overlay opened by a script's `scroll(lines)` call. Lives on `GameState::active_scroll: Option<Scroll>`; front-ends pause ticks while it's `Some` and close it via `close_scroll(choice)`. `ScrollLine` is re-exported from `action.rs` through `game.rs` so front-ends import both from `kiln_core::game`.
-- `GameState` — owns `world: World` (all boards as `Rc<RefCell<Board>>` + world scripts) and `current_board_name: String` (key of the active board). `pub log: Vec<LogLine>`, `scripts: ScriptHost`, `pub speech_bubbles: Vec<SpeechBubble>`, `pub active_scroll: Option<Scroll>`, and `pub player: Player` — the game-global player state ([`player::Player`]: `health`/`max_health`/`gems`/`keys`) that persists across board transitions (it is *not* per-board; `Board::player` holds only the per-board `PlayerPos`). `player.gems` is changed at runtime by the `alter_gems(n)` script fn (e.g. grabbing a gem); `player.health` is changed by `alter_health(dh)` (clamped to `[0, max_health]`, e.g. grabbing a heart); `player.keys` is changed by `set_key(color, present)`. Each script-hook call is handed a `ScriptState` bundle — a `Copy` snapshot of `player` plus a shared handle to the active board — passed to the hook as its `state` parameter (Rhai type `State`, read via `state.player`/`state.board`; see `api::state`). Front-ends reach the active board through `board() -> Ref<Board>` / `board_mut() -> RefMut<Board>` (both look up `world.boards[current_board_name]`). `current_board_name() -> &str` returns the active key. **`from_world(world: World) -> Self`** is the primary constructor: clones the start board's `Rc<RefCell<Board>>` for the `ScriptHost`, compiles scripts from `world.scripts`. `new(board)` and `with_scripts(board, scripts)` are `#[cfg(test)]`-only sugar that build a minimal single-board `World`. `try_move(dir)` moves the player (pushing if possible) and fires `bump(dir_from)` on the solid object it presses into — directly or at the end of a chain of crates it shoves (see `Board::bump_target`), where `dir_from` is the side the bump came from; walking onto a `grab` thing (via `Board::grab_object_at`) instead moves onto it and fires `grab()` + an immediate `resolve()` so its `die()`/`alter_gems()`/`alter_health()` apply before the call returns (no player+object overlap). **`try_move` is the only grab trigger** — a grab thing pushed or swapped into the player is an ordinary solid (it slides/blocks/refuses like any other). `run_init()` runs object `init()` hooks once at startup. `tick(dt)` advances cooldowns, expires speech bubbles, and runs `tick(dt)` hooks every frame. Both end by calling `resolve()`, which drains the board queue and applies each `Action` (`Log` → `log`, `SetTile`/`SetColor` → source glyph, `Move(dir)` → `step_object`, `Say` → `speech_bubbles`, `Scroll` → `active_scroll`, `AddGems(n)` → `player.gems`, `AlterHealth(dh)` → `player.health` clamped to `[0, max_health]`, `SetKey` → `player.keys`, `Shift` → `apply_shift`, `Push`/`Teleport` → board moves, `Send` → `run_send`, `Die` → `remove_object(source)`). Resolution is two-phase: mutate the board collecting `(bumped, dir_from)` pairs (the bumped object and the direction the bump came from), drop the borrow, then fire `run_bump` for each pair. `drain_errors()` moves script errors into `log`. `close_scroll(choice)` clears `active_scroll` and optionally fires `run_send(source, choice, None)` to dispatch the player's selection back to the object.
+- `GameState` — owns `world: World` (all boards as `Rc<RefCell<Board>>` + world scripts) and `current_board_name: String` (key of the active board). `pub log: Vec<LogLine>`, `scripts: ScriptHost`, `pub speech_bubbles: Vec<SpeechBubble>`, `pub active_scroll: Option<Scroll>`, and `pub player: Player` — the game-global player state ([`player::Player`]: `health`/`max_health`/`gems`/`keys`) that persists across board transitions (it is *not* per-board; `Board::player` holds only the per-board `PlayerPos`). `player.gems` is changed at runtime by the `alter_gems(n)` script fn (e.g. grabbing a gem); `player.health` is changed by `alter_health(dh)` (clamped to `[0, max_health]`, e.g. grabbing a heart); `player.keys` is changed by `set_key(color, present)`. Each script-hook call is handed a `ScriptState` bundle — a `Copy` snapshot of `player` plus a shared handle to the active board — passed to the hook as its `state` parameter (Rhai type `State`, read via `state.player`/`state.board`; see `api::state`). Front-ends reach the active board through `board() -> Ref<Board>` / `board_mut() -> RefMut<Board>` (both look up `world.boards[current_board_name]`). `current_board_name() -> &str` returns the active key. **`from_world(world: World) -> Self`** is the primary constructor: clones the start board's `Rc<RefCell<Board>>` for the `ScriptHost`, compiles scripts from `world.scripts`. `new(board)` and `with_scripts(board, scripts)` are `#[cfg(test)]`-only sugar that build a minimal single-board `World`. `try_move(dir)` moves the player (pushing if possible) and fires `bump(dir_from)` on the solid object it presses into — directly or at the end of a chain of crates it shoves (see `Board::bump_target`), where `dir_from` is the side the bump came from; walking onto a `grab` thing (via `Board::grab_object_at`) instead moves onto it and fires `grab()` — applied immediately — so its `die()`/`alter_gems()`/`alter_health()` take effect before the call returns (no player+object overlap). **`try_move` is the only grab trigger** — a grab thing pushed or swapped into the player is an ordinary solid (it slides/blocks/refuses like any other). `run_init()` runs object `init()` hooks once at startup. `tick(dt)` expires speech bubbles, then runs each object's `tick(dt)` hook **in ascending id order, applying that object's drained actions before the next object runs** — so a later object sees the board an earlier one just changed (the requested fix; the exception is actions still behind a `Delay`). The workhorse is `apply_actions(Vec<BoardAction>) -> Events`: two-phase (mutate the board collecting `(bumped, dir_from)` pairs, drop the borrow, then apply the player-stat / bubble / scroll changes), applying each `Action` (`Log` → `log`, `SetTile`/`SetColor` → source glyph, `Move(dir)` → `step_object`, `Say` → `speech_bubbles`, `Scroll` → `active_scroll`, `AddGems(n)` → `player.gems`, `AlterHealth(dh)` → `player.health` clamped to `[0, max_health]`, `SetKey` → `player.keys`, `Shift` → `apply_shift`, `Push`/`Teleport` → board moves, `Die` → `remove_object(source)`). It **returns** the `bump`/`send` reactions rather than firing them; after all object hooks, `settle(events, called)` runs them (and any they cascade into) until quiescent, applying each hook's actions as it goes. `called: CalledSet` (a `HashSet<(ObjectId, fn/hook name, arg repr)>`, fresh per `tick`/`try_move`/`run_init`) records every reaction fired and skips repeats, so a bump/send cycle terminates. `drain_errors()` moves script errors into `log`. `close_scroll(choice)` clears `active_scroll` and optionally fires `run_send(source, choice, None)` to dispatch the player's selection back to the object.
 
 **`kiln-core/src/action.rs`** — the `Action` enum and its supporting types:
 - `MOVE_COST: f64` — how long a move occupies an object before it can act again (0.25 s).
 - `ScrollLine` (`pub`) — one line of content in a `Scroll` action: `Text(String)` (plain, word-wrapped) or `Choice { choice, display }` (selectable; `choice` is sent back to the source object when the player picks it).
 - `SendArg` — the optional argument carried by a `Send` action / `send()` call: `None`/`Int`/`Float`/`String`, with `From<Dynamic>`/`Into<Dynamic>` conversions.
-- `Action` (`pub(crate)`) — deferred mutation emitted by a script and applied by `GameState` after promotion onto the board queue: `Move(Direction)`, `SetTile(u32)`, `Log(LogLine)`, `SetTag { target, tag, present }`, `Say(String, f64)` (bubble text + duration), `Delay(f64)` (never reaches the board queue — consumed by `ObjQueue::drain` to pace the object), `SetColor { fg, bg }`, `Send { target, fn_name, arg }`, `Scroll(Vec<ScrollLine>)`, `Teleport { x, y }`, `Push { x, y, dir }` (shove a chain at arbitrary coords; zero time cost), `Shift(Vec<(i64,i64)>)` (rotate the solids on a ring of cells one step; zero time cost), `AddGems(i64)` (change `GameState::player.gems`, clamped at 0; zero cost), `AlterHealth(i64)` (change `GameState::player.health`, clamped to `[0, max_health]`; zero cost), `SetKey(String, bool)` (give/take a named player key color; zero cost), `Die` (remove the source object; zero cost).
-- `BoardAction { source, action }` — an `Action` promoted onto the board queue, tagged with the `ObjectId` that issued it.
+- `Action` (`pub(crate)`) — deferred mutation emitted by a script, drained from the issuing object's queue and applied by `GameState::apply_actions`: `Move(Direction)`, `SetTile(u32)`, `Log(LogLine)`, `SetTag { target, tag, present }`, `Say(String, f64)` (bubble text + duration), `Delay(f64)` (never drained as an action — consumed by `ObjQueue::drain` to pace the object), `SetColor { fg, bg }`, `Send { target, fn_name, arg }`, `Scroll(Vec<ScrollLine>)`, `Teleport { x, y }`, `Push { x, y, dir }` (shove a chain at arbitrary coords; zero time cost), `Shift(Vec<(i64,i64)>)` (rotate the solids on a ring of cells one step; zero time cost), `AddGems(i64)` (change `GameState::player.gems`, clamped at 0; zero cost), `AlterHealth(i64)` (change `GameState::player.health`, clamped to `[0, max_health]`; zero cost), `SetKey(String, bool)` (give/take a named player key color; zero cost), `Die` (remove the source object; zero cost).
+- `BoardAction { source, action }` — an `Action` drained from an object's queue, tagged with the `ObjectId` that issued it; `GameState` applies a `Vec<BoardAction>` per object.
 
 **`kiln-core/src/floor.rs`** — procedural floor generators:
 - A "floor" is just a non-solid, visible `Empty` cell on a layer (a palette entry with `kind = "floor"`). This module only owns the generators; the actual per-cell placement happens in `layer.rs` during load.
@@ -89,12 +89,12 @@ The core types that were formerly monolithic in `game.rs` are now split into foc
 
 **`kiln-core/src/script.rs`** — Rhai scripting **host** (the script-facing types live in `kiln-core/src/api/`, below). The script-author's reference is [`docs/script-api.md`](../docs/script-api.md).
 - `Registerable` trait — `fn register(engine, error_sink)`: a type's hook for installing itself (Rhai type name + getters/methods) on the `Engine`. Implemented by every `api` type plus `Glyph`/`Keyring`.
-- `ScriptHost` — owns the Rhai `Engine`, the compiled scripts (`HashMap<String, CompiledScript>`), one persistent `Scope` per scripted object (`HashMap<ObjectId, Scope>`), the shared board queue, and the error sink. Built with `ScriptHost::new(&Rc<RefCell<Board>>, &HashMap<String, String>)`: the first arg is a shared ref to the active board (cloned into the write-API closures and each scope's `Registry`), the second is the world-level script pool. Each script is compiled once per `script_key` (the object's `script_name` — a world-pool name, or a synthetic `BUILTIN_*` name assigned by `expand_builtin_archetypes` so identical built-ins share one AST); the source is the pool entry for that key, or the object's embedded `builtin_script`. `CompiledScript` records which hooks the AST defines (`has_init`/`has_tick`/`has_bump`/`has_grab`). **Per-object output queues no longer live here** — each `ObjectDef` owns its `queue: ObjQueue`. Reports compile/unknown-script failures onto the error sink; runs nothing.
-- Lifecycle hooks, each taking `me` (an `ObjectInfo`) and `state` (a `ScriptState`) before any hook-specific arg: `init(me, state)`, `tick(me, state, dt)`, `bump(me, dir)` (`dir` is the `Direction` the bump came *from*, fired when any solid — the player, another object, or a pushed crate — presses into this object), and `grab(me, state)` (fired when the player walks onto a `grab` thing — the only grab trigger). All optional — detected via `AST::iter_functions()` by name **and arity** (bump is arity 2). Driven by `run_init(state)` / `run_tick(state, dt)` / `run_bump(id, dir)` / `run_grab(state, id)`, all funneling through `run_hook_on_one`: it builds a fresh `ObjectInfo` for the object, pushes `[me, state, (arg)]`, and calls the hook tagged with the object's id. After the call — **whether or not the hook is defined** — it always drains the object's queue, so a delay still advances on an object that has no `tick`. Runtime errors go to the error sink (drained to the log), not fatal.
+- `ScriptHost` — owns the Rhai `Engine`, the compiled scripts (`HashMap<String, CompiledScript>`), one persistent `Scope` per scripted object (`HashMap<ObjectId, Scope>`), and the error sink. (There is no shared board queue: each hook call drains into a local `Vec<BoardAction>` that it returns to `GameState`.) Built with `ScriptHost::new(&Rc<RefCell<Board>>, &HashMap<String, String>)`: the first arg is a shared ref to the active board (cloned into the write-API closures and each scope's `Registry`), the second is the world-level script pool. Each script is compiled once per `script_key` (the object's `script_name` — a world-pool name, or a synthetic `BUILTIN_*` name assigned by `expand_builtin_archetypes` so identical built-ins share one AST); the source is the pool entry for that key, or the object's embedded `builtin_script`. `CompiledScript` records which hooks the AST defines (`has_init`/`has_tick`/`has_bump`/`has_grab`). **Per-object output queues no longer live here** — each `ObjectDef` owns its `queue: ObjQueue`. Reports compile/unknown-script failures onto the error sink; runs nothing.
+- Lifecycle hooks, each taking `me` (an `ObjectInfo`) and `state` (a `ScriptState`) before any hook-specific arg: `init(me, state)`, `tick(me, state, dt)`, `bump(me, dir)` (`dir` is the `Direction` the bump came *from*, fired when any solid — the player, another object, or a pushed crate — presses into this object), and `grab(me, state)` (fired when the player walks onto a `grab` thing — the only grab trigger). All optional — detected via `AST::iter_functions()` by name **and arity** (bump is arity 2). Run one object at a time (the per-object loop lives in `GameState`): `run_tick_on(id, dt)` / `run_init_on(id)` / `run_bump(id, dir)` / `run_grab(id)` / `run_send(id, fn, arg)`, all funneling through `run_hook_on_one` and **returning the `Vec<BoardAction>` they drained** for `GameState` to apply. `run_hook_on_one` builds a fresh `ObjectInfo`, pushes `[me, state, (arg)]`, and calls the hook tagged with the object's id. After the call — **whether or not the hook is defined** — it always drains the object's queue, so a delay still advances on an object that has no `tick`. Runtime errors go to the error sink (drained to the log), not fatal.
 - `run_send(state, id, fn_name, arg)` — calls an arbitrary named function on an object (backs the `send()` action and scroll-choice dispatch). Picks the param list by the function's arity: 3 → `(me, state, arg)`, 2 → `(me, state)`, 1 → `(arg)`, 0 → `()`; a missing arg is `Dynamic::UNIT`. Errors if no function of that name exists.
 - **Reads** are methods/getters on the `api` types handed to the hook — `state.player.*`, `state.board.*`, `me.*` (see the `api/` section). There are **no read free functions** anymore.
 - **Write API** (`register_write_api`) — free functions that enqueue an `Action` onto the **issuing object's** `queue` (resolved from the per-call tag): `move(dir)` (enqueues `Move` then a `MOVE_COST` delay), `delay(secs)`/`now()` (queue pacing), `set_tile(n)`, `set_fg`/`set_bg`/`set_color`, `set_tag(target, tag, present)`, `log(s)`, `say(s)`/`say(s, dur)`, `scroll(lines)`, `send(target, fn [, arg])`, `teleport(id, x, y)` (jump entity `id` to a cell; `me.id` = self, `-1` = player), `push(x, y, dir)`, `shift([[x, y], …])`, `alter_gems(n)`, `alter_health(dh)`, `set_key(color, present)`, `die()`. `scroll(lines)` takes a Rhai array whose elements are a string (text line) or a two-element `[choice_key, display_text]` (selectable choice). `shift` takes an array of two-int `[x, y]` arrays (a malformed entry logs an error) and rotates that ring of cells via `Board::apply_shift`.
-- **Queue draining (two-tier):** each object's actions sit in its own `ObjQueue` until `ObjectInfo::drain(board_queue, dt)` promotes them onto the shared **board queue** (`Vec<BoardAction>`): it first eats leading `Delay` actions with `dt` (a delay longer than `dt` is decremented and stops the drain — this caps object speed), then moves the run of ready actions across. `GameState` takes the board queue with `take_board_queue()` and applies it after the batch, so scripts mutate without a `&mut GameState` borrow. Errors bypass the queues via the error sink (`take_errors()`).
+- **Queue draining:** each object's actions sit in its own `ObjQueue` until `ObjectInfo::drain(&mut Vec<BoardAction>, dt)` moves its ready run into a caller-supplied `Vec`: it first eats leading `Delay` actions with `dt` (a delay longer than `dt` is decremented and stops the drain — this caps object speed), then moves the run of ready actions across. The hook runner returns that `Vec` and `GameState` applies it immediately (per object), so scripts mutate without a `&mut GameState` borrow and each object sees the prior object's effects. Errors bypass the queue via the error sink (`take_errors()`).
 - **Constants in scope:** only `Registry` is pushed into each object's scope (the `me`/`state` views are hook *parameters* now). `register_global_constants` registers the `North`/`South`/`East`/`West` `Direction` values and the 16 named colors as a **global module**, visible at any call depth (including Rhai→Rhai calls and helper functions) — unlike scope constants such as `Registry`.
 - `Registry` (a `Board`-handle wrapper) — `Registry.get(key)` / `set(key, value)` / `get_or(key, default)` read and write the board's `registry: HashMap<String, RegistryValue>`, which **persists across board transitions**. `set(key, ())` removes a key; unsupported value types are ignored; `get_or` only returns the stored value when it matches the default's Rhai type.
 - **Sender identity uses stable ids:** the issuing `ObjectId` rides the per-call **tag** — `run_*` calls `call_fn_with_options(...with_tag(id)...)` and the write fns read it via `NativeCallContext::tag()` (decoded by `source_of`; id 0, never valid, is the no-source fallback). It matches `Board::objects`' `BTreeMap` keys, so it survives object spawn/destroy/reorder.
@@ -104,8 +104,8 @@ The core types that were formerly monolithic in `game.rs` are now split into foc
 - `api::state` — `ScriptState { player: PlayerWithPos, board: BoardRef }` (Rhai type **`State`**), the `state` parameter of every hook. `from_game_state` snapshots the player and clones the board handle; getters `state.player` / `state.board`.
 - `api::player` — `PlayerWithPos(Player, PlayerPos)` (Rhai type **`Player`**), a `Copy` bundle of the game-global `Player` stats and the per-board `PlayerPos` so they register as one Rhai object. Getters `gems`, `health`, `max_health`, `keys` (a `Keyring`, exposing one `bool` getter per color), `x`, `y`.
 - `api::board` — `BoardRef = Rc<RefCell<Board>>` (Rhai type **`Board`**), a read-only handle. Getters `width`/`height`; methods `can_push(x, y, dir)`, `passable(x, y)`, `get(id)` (→ `ObjectInfo` or `()`; `id <= 0` logs an error), `named(name)` (→ `ObjectInfo` or `()`), `tagged(tag)` (→ array of `ObjectInfo`).
-- `api::object_info` — `ObjectInfo` (a snapshot of one object: `id`, `x`, `y`, a board handle, `script_name`, and a clone of the object's `ObjQueue`), used as both the `me` parameter and the return type of the `Board` lookups (so self and other objects are the **same** type). Getters `x`/`y`/`id`/`name`/`tags`/`glyph`/`waiting`/`queue`; methods `has_tag(tag)`, `delay(secs)`, `can_push(dir)`, `blocked(dir)`. `from_id`/`from_def` build it; `drain(target, dt)` promotes the underlying object's queued actions onto the board queue.
-- `api::queue` — `ObjQueue(Rc<RefCell<VecDeque<Action>>>)` (Rhai type **`Queue`**), one object's output queue, owned by its `ObjectDef` and reachable as `me.queue`. Rhai surface: getter `length`, methods `clear()`, `delay(secs)`. Rust surface used by the host: `act`, `delay` (merges a trailing delay), `now` (promote the last-enqueued action to the front), `drain` (eat leading delays by `dt`, then promote ready actions), `waiting` (front is a `Delay`).
+- `api::object_info` — `ObjectInfo` (a snapshot of one object: `id`, `x`, `y`, a board handle, `script_name`, and a clone of the object's `ObjQueue`), used as both the `me` parameter and the return type of the `Board` lookups (so self and other objects are the **same** type). Getters `x`/`y`/`id`/`name`/`tags`/`glyph`/`waiting`/`queue`; methods `has_tag(tag)`, `delay(secs)`, `can_push(dir)`, `blocked(dir)`. `from_id`/`from_def` build it; `drain(&mut Vec<BoardAction>, dt)` moves the underlying object's ready queued actions into the target `Vec`.
+- `api::queue` — `ObjQueue(Rc<RefCell<VecDeque<Action>>>)` (Rhai type **`Queue`**), one object's output queue, owned by its `ObjectDef` and reachable as `me.queue`. Rhai surface: getter `length`, methods `clear()`, `delay(secs)`. Rust surface used by the host: `act`, `delay` (merges a trailing delay), `now` (promote the last-enqueued action to the front), `drain` (eat leading delays by `dt`, then move the ready actions into a `&mut Vec<BoardAction>`), `waiting` (front is a `Delay`).
 
 **`kiln-core/src/map_file.rs`** — per-board serde shell + load/save orchestration (the bulk of the per-layer work lives in `layer.rs`):
 - `MapFile { map: MapHeader, layers: Vec<LayerData> }` — serde for one board: a `[map]` header (`name`, `width`, `height`, optional `board_script_name`; **no** `player_start` — the player is a `kind = "player"` palette char) plus the `[[layers]]` stack. Does **not** include scripts (those live in `World::scripts`).