added blocking doors to paths.

src/scripts/enemy_rat.gd

@@ -19,6 +19,9 @@ func _ready():
 	damage = 8.0
 	
 	state_timer = idle_duration
+	
+	# CRITICAL: Ensure collision mask is set correctly (walls are on layer 7 = bit 6 = 64)
+	collision_mask = 1 | 2 | 64  # Collide with players (layer 1), objects (layer 2), and walls (layer 7 = bit 6 = 64)
 
 func _ai_behavior(delta):
 	# Update state timer