fix(ui): resolve HUD layout overlaps (#792)

- DebugOverlay: position comment updated, tscn is source of truth
- GauntletHUD: moved from y:48 to y:252 (below StanceIndicator)
- StanceIndicator: offset_top 192→200, height 26→44px for ImplantPanel

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

client/ui/debug_overlay.gd

@@ -76,7 +76,7 @@ var _tick_deltas: Array = []  # ms between consecutive snapshots
 func _ready() -> void:
 	_dev_mode = OS.is_debug_build()
 	visible = false
-	position.y = 150.0  # Below TimeDisplay (16-70) + HUD status panel (80-140)
+	# Position set in main.tscn: below merged HUD status panel (starts at y:16)
 	_cached_font = ThemeDB.fallback_font
 	# Clear NPC path history on session change to prevent entity ID collisions
 	GameState.connect("game_id_changed", _on_game_id_changed)