fix(ui): address PR #115 review — 8 items

- Fix stale test path UILayer/HUD → InsertOverlay/HUD
- Fix D-record citation D-051 → D-049 in main.tscn
- Add null guards to hud.gd update methods (pre-_ready safety)
- Minimap: dirty-flag queue_redraw instead of per-frame
- Remove redundant _panel.size.x, debug print
- Fix DebugOverlay/GauntletHUD positioning comments

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

client/ui/hud.gd

@@ -21,7 +21,6 @@ func _ready() -> void:
 	_panel.name = "StatusPanel"
 	_panel.theme_resource = theme_res
 	_panel.custom_minimum_size.x = 200.0
-	_panel.size.x = 200.0
 	_panel.mouse_filter = Control.MOUSE_FILTER_IGNORE
 	_panel.position = Vector2(16, 16)  # top-left; replaces standalone TimeDisplay
 	add_child(_panel)
@@ -34,10 +33,10 @@ func _ready() -> void:
 	_panel.add_component(_health_row)
 	_panel.add_component(_perception_row)
 
-	print("HUD: Initialized")
-
 
 func update_from_hud_data(data: Dictionary) -> void:
+	if not _perception_row:
+		return
 	if data.has("perception_mode"):
 		var prefix := UIStrings.get_text("hud.perception_mode_prefix")
 		if prefix.is_empty():
@@ -47,10 +46,14 @@ func update_from_hud_data(data: Dictionary) -> void:
 
 
 func update_health(health: int) -> void:
+	if not _health_row:
+		return
 	_health_row.text = UIStrings.get_text("hud.health") + ": " + str(health)
 
 
 func update_from_state() -> void:
+	if not _time_row:
+		return
 	var gt: Dictionary = GameState.game_time
 	if gt.is_empty():
 		return