feat: Introduce EnhancedGridMap addon for advanced grid management and procedural generation, and StaticTektonManager for tekton spawning and placement.

scripts/managers/special_tiles_manager.gd

@@ -382,6 +382,21 @@ func _execute_block_floor(target_pos: Vector2i):
 		var pos = n.position
 		var block_pos = Vector3i(pos.x, 0, pos.y)
 		
+		# Check current item first
+		var current_item = enhanced_gridmap.get_cell_item(block_pos)
+		
+		# Skip if already a wall or immutable
+		# We assume Item 4 is the wall/stand. 
+		# Also check enhanced_gridmap.immutable_items if available
+		var is_immutable = false
+		if "immutable_items" in enhanced_gridmap:
+			if current_item in enhanced_gridmap.immutable_items:
+				is_immutable = true
+		
+		if current_item == 4 or is_immutable:
+			# Don't overwrite existing walls/stands, and don't schedule them for "restoration" (deletion)
+			continue
+			
 		if player.is_multiplayer_authority():
 			var main = player.get_tree().get_root().get_node_or_null("Main")
 			if main:
@@ -390,7 +405,7 @@ func _execute_block_floor(target_pos: Vector2i):
 		# Record for restoration
 		blocked_tiles.append({
 			"position": block_pos,
-			"original_item": 0,
+			"original_item": current_item, # Restore the ACTUAL item that was there (e.g. ground 0 or maybe a dropped item?)
 			"timer": BLOCK_DURATION
 		})