feat: Add PlayerActionManager for handling player actions and highlights, and SpecialTilesManager for managing special tile effects and powerups.

scripts/managers/player_action_manager.gd

@@ -85,8 +85,9 @@ func highlight_cells_if_authorized(cells_to_highlight: Array, item_id: int = -1)
 	
 	for cell in cells_to_highlight:
 		highlighted_cells.append(cell)
+		# Use Layer 2 for overlay highlights (prevents overwriting walls on Layer 0)
 		enhanced_gridmap.set_cell_item(
-			Vector3i(cell.x, 0, cell.y),
+			Vector3i(cell.x, 2, cell.y),
 			highlight_item
 		)
 
@@ -182,10 +183,25 @@ func clear_highlights():
 	# Store the current action state before clearing
 	var main = player.get_tree().get_root().get_node_or_null("Main")
 	var current_state = main.ui_manager.current_action_state if main else null
-
+	
+	var hover_id = enhanced_gridmap.hover_item
+	
 	for cell in highlighted_cells:
 		if cell is Vector2i:
-			enhanced_gridmap.set_cell_item(Vector3i(cell.x, 0, cell.y), enhanced_gridmap.normal_items[0])
+			# Check Layer 2 (Overlay Highlight)
+			var l2_pos = Vector3i(cell.x, 2, cell.y)
+			var l2_item = enhanced_gridmap.get_cell_item(l2_pos)
+			# Only clear if it looks like a highlight (e.g. ID 1) 
+			# or generally just clear layer 2 if we assume we own it for highlights? 
+			# Safest is to check against hover_id or typical highlight IDs.
+			if l2_item != -1:
+				enhanced_gridmap.set_cell_item(l2_pos, -1)
+			
+			# Check Layer 0 (Floor Highlight)
+			var l0_pos = Vector3i(cell.x, 0, cell.y)
+			var l0_item = enhanced_gridmap.get_cell_item(l0_pos)
+			if l0_item == hover_id:
+				enhanced_gridmap.set_cell_item(l0_pos, enhanced_gridmap.normal_items[0])
 	
 	highlighted_cells.clear()