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/tests/test_rendering.gd

@@ -298,25 +298,30 @@ func test_entity_renderer_player_has_facing_indicator() -> void:
 	renderer.queue_free()
 
 func test_entity_renderer_facing_indicator_rotation_accuracy() -> void:
+	# D-054: Facing indicator now reads InputMapper.facing_angle (float), not
+	# GameState.player_facing (string). Indicator rotation = facing_angle + PI/2.
 	GameState.player_entity_id = 1
 	var renderer := _make_entity_renderer()
-	var directions := {
-		"North": 0.0,
-		"Northeast": PI / 4.0,
-		"East": PI / 2.0,
-		"Southeast": 3.0 * PI / 4.0,
-		"South": PI,
-		"Southwest": 5.0 * PI / 4.0,
-		"West": 3.0 * PI / 2.0,
-		"Northwest": 7.0 * PI / 4.0,
+	# {facing_angle → expected indicator rotation}
+	# Indicator 0 = North (up). facing_angle 0 = East. So rotation = angle + PI/2.
+	var angles := {
+		-PI / 2.0: 0.0,            # North
+		-PI / 4.0: PI / 4.0,       # Northeast
+		0.0: PI / 2.0,             # East
+		PI / 4.0: 3.0 * PI / 4.0,  # Southeast
+		PI / 2.0: PI,              # South
+		3.0 * PI / 4.0: 5.0 * PI / 4.0,  # Southwest
+		PI: 3.0 * PI / 2.0,       # West
+		-3.0 * PI / 4.0: 7.0 * PI / 4.0,  # Northwest (note: -PI/2 wraps)
 	}
 	renderer.update_entities(_test_entities_v2)
 	var player_node = renderer.entity_nodes[1]
 	var indicator = player_node.get_node_or_null("FacingIndicator")
-	for dir_name in directions:
-		GameState.player_facing = dir_name
+	for angle in angles:
+		InputMapper.facing_angle = angle
 		renderer.update_entities(_test_entities_v2)
-		assert_that(indicator.rotation).is_equal_approx(directions[dir_name], 0.001)
+		assert_that(indicator.rotation).is_equal_approx(angles[angle], 0.001)
+	InputMapper.facing_angle = -PI / 2.0  # Reset to default (North)
 	renderer.queue_free()
 
 func test_entity_renderer_npc_has_no_facing_indicator() -> void: