feat: Add core player input, movement, and special ability management systems with new UI components.

scripts/managers/stop_n_go_manager.gd

@@ -20,7 +20,7 @@ var safe_zone_centers: Array[Vector2i] = []
 var safe_zone_spawned: bool = false
 
 # Power-Up Tile Spawning
-const POWERUP_TILES = [11, 14] # Speed (11) and Ghost (14)
+const POWERUP_TILES = [11, 12, 13, 14] # Speed, Freeze, Wall, Ghost
 const POWERUP_SPAWN_COUNT: int = 5 # Number of power-up tiles to spawn
 var powerups_spawned: bool = false
 var stop_phase_occurred: bool = false
@@ -362,7 +362,7 @@ func _spawn_mission_tiles():
 			var current_item = gridmap.get_cell_item(Vector3i(x, 1, z))
 			
 			# PROTECTED FLOOR CHECK: Don't spawn on walls or void
-			if base_tile in [TILE_OBSTACLE, -1] or current_item == TILE_OBSTACLE or current_item == 13:
+			if base_tile in [TILE_OBSTACLE, -1] or current_item == TILE_OBSTACLE:
 				continue
 				
 			# Spawn tiles with 60% density