fix(client): address PR #141 review — parse-order, tween guard, test fixes

- Fix autoload parse-order violations: sim_bridge.gd, input_mapper.gd,
  audio_manager.gd now use load() for class_name types instead of
  direct references (LocalBridge, ServerProcess, Constants)
- Collapse redundant tween validity guard in dialogue_box.gd to
  is_instance_valid(panel) only
- Add clarifying comments to fog test resize assertions (8-tile
  padding trigger, 32x32 fixture assumption)
- Fix test_examine_display_sprint18 case 2: GameState.has() →
  "field" in GameState (Node vs Dictionary API)
- Fix test_game_state_sprint20: rename before_each → before_test
  (GdUnit4 lifecycle hook)

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

client/tests/test_examine_display_sprint18.gd

@@ -52,7 +52,7 @@ func after_test() -> void:
 # ---------------------------------------------------------------------------
 
 func test_gamestate_examine_result_field_exists() -> void:
-	assert_bool(GameState.has("current_examine_result")).override_failure_message(
+	assert_bool("current_examine_result" in GameState).override_failure_message(
 		"GameState must have 'current_examine_result' field (#174)"
 	).is_true()
 

client/tests/test_fog_sprint22.gd

@@ -25,6 +25,7 @@ func _reset_fog_state(fog_state: Node) -> void:
 	GameState.boundary_positions.clear()
 	GameState.visible_tiles.clear()
 	GameState.visibility_sectors.clear()
+	# 32x32 is an arbitrary test fixture size — not a production assumption.
 	fog_state._resize(Rect2i(0, 0, 32, 32))
 
 
@@ -220,7 +221,8 @@ func test_exploration_data_preserved_across_resize() -> void:
 	GameState.visible_positions = {Vector2i(3, 3): true}
 	fog_state.update_from_state()
 
-	# Force a resize by moving far away
+	# Move far enough to trigger a resize: _grow_bounds_from_positions adds 8-tile padding,
+	# so (25,25) expands the bounds beyond the 32x32 fixture set in _reset_fog_state.
 	GameState.visible_positions = {Vector2i(25, 25): true}
 	fog_state.update_from_state()
 
@@ -250,7 +252,8 @@ func test_newly_added_area_starts_unexplored_after_resize() -> void:
 	GameState.visible_positions = {Vector2i(2, 2): true}
 	fog_state.update_from_state()
 
-	# Move far away to trigger bounds growth
+	# Move far enough to trigger a resize: _grow_bounds_from_positions adds 8-tile padding,
+	# so (30,30) expands the bounds beyond the 32x32 fixture set in _reset_fog_state.
 	GameState.visible_positions = {Vector2i(30, 30): true}
 	fog_state.update_from_state()
 

client/tests/test_game_state_sprint20.gd

@@ -12,7 +12,7 @@ class_name TestGameStateSprint20
 extends GdUnitTestSuite
 
 
-func before_each() -> void:
+func before_test() -> void:
 	GameState.stationary_ticks = 0
 	SnapshotHandler._prev_player_position = Vector2(-1e9, -1e9)
 	GameState.current_zone_id = ""