Add Phase 3a Core Director Functionality

- Introduced `PHASE_3a_CORE_DIRECTOR.md` detailing the core functionality for directors, including navigation, action queue, UI, waypoint visualization, and action execution.
- Implemented `StageDirectorVisuals` for drawing stickman action queues in edit mode, including waypoints and action badges.
- Created `SpeechBubble` class for displaying speech bubbles above stickmen, with customizable text and styling.

AGENTS.md

@@ -300,6 +300,43 @@ assembled in a "Whole Stickman" preview that supports translation, rotation, and
     `set_ragdoll(false)` during `RAGDOLL` routes through `_start_recovery()`; repeated
     `set_ragdoll` calls are idempotent. `is_in_ragdoll()` stays
     `state == RigState.RAGDOLL` (so `RECOVERING` reads as "Stickman").
+  - **Phase 3a director functionality:** adds navigation/walking, speech, an action queue, and a
+    queue-runner state machine. Enums `RunnerState { IDLE, EXECUTING }` and `ActionPhase { NONE,
+    WALKING, SPEAKING, WAITING, RAGDOLLING, RECOVERING }`. Constants `FOOT_OFFSET := (0, -385)`
+    (feet → root; matches `StageSpawner.STICKMAN_FOOT_OFFSET`), `NAV_AGENT_LOCAL_POS := (0, 385)`
+    (`== -FOOT_OFFSET`), `ARRIVE_DISTANCE` / `NAV_PATH_DESIRED_DISTANCE` / `NAV_TARGET_DESIRED_DISTANCE`
+    / `SPEECH_BUBBLE_OFFSET`. New signals `arrived`, `action_started(action, index)`,
+    `action_finished(action, index)`, `queue_finished` (on completion, not stop), `queue_changed`
+    (any queue mutation), `speech_finished`. Exports `walk_speed` (300.0). Public API: `walk_to(
+    target, speed = -1.0)` (feet/ground destination; no-op unless `state == ANIMATED`), `is_walking()`,
+    `speak(text, duration)` (lazily creates a `SpeechBubble` child at `SPEECH_BUBBLE_OFFSET`, auto-hides
+    + emits `speech_finished`), the queue API `queue_action` / `clear_queue` / `get_queue` /
+    `remove_action` / `insert_action` / `queue_size` (all mutations emit `queue_changed`), and the
+    runner API `start_queue` / `stop_queue` / `is_queue_running`. `_ready()` builds a
+    `NavigationAgent2D` child at `NAV_AGENT_LOCAL_POS` (feet, on the ground-level nav mesh;
+    `avoidance_enabled = false`, `max_speed = walk_speed`, shared default nav map layer 1). A
+    `_physics_process` ordering of `_track_momentum` → `_update_rest_detection` → `_update_walking`
+    → `_update_speech` → `_update_runner` drives the runner state machine per `ActionPhase`
+    (`walk_to` → wait for `_walk_done`; `speak` → wait for `!_speech_active`; `wait` → `_phase_timer`
+    countdown; `ragdoll` → `set_ragdoll(true)` then wait `is_ragdoll_at_rest()`; `recover` →
+    `request_recovery()` then wait `state == ANIMATED`). `is_ragdoll_at_rest()` is a new public
+    query exposing the rest result **regardless of `auto_recover`** (the runner polls it; auto-recovery
+  logic is unchanged). `_enter_ragdoll()` additionally calls `_cancel_walking()` (no stale walk/path
+  state) and resets `_ragdoll_at_rest = false`. **Walk fix (2026-08-29, hybrid policy):**
+  `_update_walking` defers all nav reads until `NavigationServer2D.map_get_iteration_id(...) != 0`
+  (map-sync guard), forces the path query via `get_next_path_position()` **before** any empty-path /
+  finished check (the read-only `get_current_navigation_path()` alone never triggers a
+  repath), then branches on `is_target_reachable()`: an **on-mesh target** follows the nav path
+  (`_walk_mode = "nav"`), while an **off-mesh/unreachable target** switches to **direct
+  straight-line steering** toward the clicked waypoint (`_walk_mode = "direct"`, root target =
+  waypoint + `FOOT_OFFSET`) — a supported case with **no** `push_warning` (the old "warn + finish
+  in place" policy was replaced; the rig never stands still at a waypoint). There is **no**
+  `_walk_path_grace` variable (the map-sync guard + forced path query replace it) and **no
+  unreachable warning**; the debug trace now carries a `mode=nav|direct` field. Off-by-default
+  diagnostics: `DEBUG_WALK` + `_walk_dbg()` (rig) and `DEBUG_STAGE` + `_stage_dbg()` (sandbox_stage).
+  Walking is kinematic
+  (`global_position.move_toward`); movement composes with the `walk_left`/`walk_right` in-place limb
+  animations (each has a discrete `.:facing_profile` track).
 - `scripts/stickman_factory.gd` — `class_name StickmanFactory`, `extends RefCounted`; a **static
   factory** and the **runtime entry point** (Phase 9, **not used by the editor**) that turns a
   `.stk` file into a live, rigged `master_rig.tscn` instance:
@@ -562,6 +599,44 @@ assembled in a "Whole Stickman" preview that supports translation, rotation, and
   Grid/Snap/Size controls, status label. The build controls (spawn palette + Grid/Snap/Size) are
   hidden in PLAY via `_set_build_controls_visible()`, called from `_enter_edit_mode()` /
   `_enter_play_mode()` (the mode toggle and status label stay visible).
+  - **Phase 3a director tool:** adds a **"Direct"** palette toggle button (mutually exclusive with
+    placement) and a `PopupMenu` (`_action_popup`, items `Walk To`/`Speak`/`Wait`/`Ragdoll`/`Recover`,
+    ids `ACT_WALK`…`ACT_RECOVER`) opened by clicking a stickman (`_handle_direct_click`); speak/wait
+    `AcceptDialog`s append `speak`/`wait` actions; `Walk To` enters a pending target-capture mode whose
+    next stage click appends `{"type":"walk_to","target":world_pos}` and which **Esc** cancels (Esc
+    priority: pending target → exit direct mode → existing placement clears). Builds a code-built
+    `NavigationRegion2D` (`_build_navigation()`, child of the stage **not** `World` so it is never
+    hit-tested) carrying a procedural `NavigationPolygon` from per-`TerrainBlock` convex decomposition
+    (`_rebake_navigation()`, `Geometry2D.decompose_polygon_in_convex` + fan triangulation, world-space
+    via `block.transform * p`); a `_nav_dirty` flag re-bakes once per frame (`_process`) on terrain
+    place / move / rotate (`transform_committed`) / delete. Instantiates a `StageDirectorVisuals`
+    overlay (`_build_director_visuals()`). **Play mode change (D3):** `_enter_play_mode()` no longer
+    auto-ragdolls stickmen — it now sets each rig `auto_recover = false` and calls `start_queue()`;
+    `ragdoll`/`recover` are explicit queue actions; props still unfreeze. `_enter_edit_mode()`
+    `stop_queue()`s then `snap_to_standing()`s stickmen and re-enables the visuals. Wires
+    `node.queue_changed → _director_visuals.mark_dirty` when a stickman is placed; `object_deleted` →
+    `mark_dirty()`. `_set_build_controls_visible()` also hides the Direct button in PLAY.
+- `scripts/stickman_speech_bubble.gd` — `class_name SpeechBubble`, `extends Node2D`; a **world-space
+  speech bubble** drawn in `_draw()` (Phase 3a, **not used by the editor**). Child of a `StickmanRig`
+  at `SPEECH_BUBBLE_OFFSET` (above the head), so it follows the figure and scales with the camera.
+  Consts `FONT_SIZE`/`PADDING`/`TAIL_HEIGHT`/`MAX_WIDTH`/`BG_COLOR`/`BORDER_COLOR`/`TEXT_COLOR`.
+  Measures text via `ThemeDB.fallback_font.get_string_size(...)`, draws a rounded-rect background +
+  a downward tail triangle centered on the rig-local origin, then `draw_string(...)`; `visible = false`
+  by default, no hit-testing. Public API: `show_text(text)` (store, `visible = true`, `queue_redraw()`),
+  `hide_bubble()`. Driven by `StickmanRig.speak()`; the rig owns hiding + the `speech_finished` signal.
+- `scripts/stage_director_visuals.gd` — `class_name StageDirectorVisuals`, `extends Node2D`; the
+  **Edit-mode director overlay** (Phase 3a, **not used by the editor**), mirroring `StageGrid`/
+  `StageGizmos`. State `camera`/`world`/`enabled`/`_dirty`; public `set_enabled(value)` /
+  `mark_dirty()`. `_process()` redraws on a dirty flag; `_draw()` reads each rig's queue via
+  `_collect_rigs()` (direct `World` children filtered `is StickmanRig`). Per action in order:
+  `walk_to` → a blue waypoint dot (`WAYPOINT_RADIUS_PX / _zoom()`) with white outline + order number at
+  `action["target"]`; dashed connectors (`draw_dashed_line`, `DASH_*` / `_zoom()`) between consecutive
+  dots (and from the rig's current feet position to the first dot); non-walk actions (`speak`/`wait`/
+  `ragdoll`/`recover`) → a badge (speech bubble / clock / X / up-arrow glyph + order number) anchored
+  at the **stickman's position at that point in the sequence** — derived by simulating the queue
+  (start at rig feet + `FOOT_OFFSET`; each `walk_to` advances the anchor; non-walk anchors at the
+  current position), consecutive badges stacking `(0, -28)/zoom`. All sizes divided by `_zoom()` so
+  markers stay screen-constant; pure `_draw()`, no hit-testing; hidden in PLAY via `set_enabled(false)`.
 - `scripts/stage_spawner.gd` — `class_name StageSpawner`, `extends RefCounted`; registry-driven
   spawner (Phase 2). A `_registry: Array[Dictionary]` maps ids to terrain/prop/stickman templates;
   adding a type = appending an entry (no hard-coded id `match`). Reuses `TerrainUtils.spawn_block`,