fix(client): address PR #36 review — 10 items from Hoshe + Tyre

Critical:
- deactivate_insert() now called when selecting non-Insert spoke,
  cancelling with no selection, or pressing Escape while insert is
  active. Fixes simulation staying paused permanently after Insert.

Warnings:
- Checklist conditions with empty id excluded from get_results() and
  get_total_count() — prevents impossible-to-complete checklists.
  Warns at load time when empty-id conditions are found.
- _content_base now checks res://content/ first (exported builds),
  falls back to ../content for editor/dev mode.
- 26 new tests for D-054 functions: _angle_to_octant (8 octants),
  _snap_to_octant_dir (9 cases incl. zero/tiny), _wasd_to_world_dir
  (8 facing/movement combos). New test file: test_input_mapper_facing.gd.

Suggestions:
- Cached get_theme_default_font() in checklist overlay _ready().
- Documented InputMapper → GameState coupling as intentional.
- Documented YAML parser # truncation limitation.
- _insert_active reset on Escape dismiss (Tyre #3).
- SimBridge test mode SetFacing reads action_data.facing instead of
  InputMapper global (Tyre #4).
- Removed dead _facing_to_rotation() from entity_renderer.gd (Tyre #5).
- Fixed 2 failing facing indicator tests to use InputMapper.facing_angle
  instead of GameState.player_facing.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

client/scripts/autoloads/sim_bridge.gd

@@ -177,7 +177,16 @@ func send_input(player_input: Dictionary) -> Error:
 		var action: int = player_input.get("action", -1)
 		var wire_name: String = _action_enum_to_wire(action)
 		if not wire_name.is_empty():
-			_test_input_queue.append(wire_name)
+			if wire_name == "SetFacing":
+				# D-054: Use action_data.facing from the input dict, not InputMapper global
+				var facing: String = ""
+				var action_data: Variant = player_input.get("action_data")
+				if action_data is Dictionary:
+					facing = str(action_data.get("facing", ""))
+				if not facing.is_empty():
+					_test_facing = facing
+			else:
+				_test_input_queue.append(wire_name)
 		return OK
 	var action_name := _action_enum_to_wire(player_input.get("action", -1))
 	if action_name.is_empty():
@@ -282,18 +291,11 @@ func _test_snapshot() -> Dictionary:
 			if dist <= 2 and _test_has_los(_test_player_pos, npc_pos):
 				_test_in_dialogue = true
 			continue
-		if action_name == "SetFacing":
-			# D-054: facing update handled separately — octant comes from InputMapper
-			_test_facing = InputMapper.facing_octant
-			continue
 		var delta := _action_to_delta(action_name)
 		var new_pos := _test_player_pos + delta
 		if _test_is_walkable(new_pos):
 			_test_player_pos = new_pos
 			if delta != Vector2i.ZERO:
-				# D-054: Facing is now mouse-driven, not movement-driven.
-				# Use InputMapper's octant instead of deriving from movement delta.
-				_test_facing = InputMapper.facing_octant
 				# Walk-away dismisses dialogue (D-064)
 				if _test_in_dialogue:
 					_test_in_dialogue = false