fix(M00): release GUI capture render resources

Work-Package: M00-QAR-GUI-RID-SHUTDOWN-001
Agent: sindo-main-codex
Tests: render baseline dry-run; runtime cache shutdown; comparator self-test; coordination and documentation gates
Fidelity: shutdown-only ownership fix; no visual or Blizzlike335 behavior change

src/scenes/streaming/streaming_world_loader.gd

@@ -374,6 +374,39 @@ func _exit_tree() -> void:
 	_shutting_down = true
 	_wait_for_tile_tasks()
 	_clear_streamed_world()
+	_release_runtime_caches_for_shutdown()
+
+
+## Frees detached prototype nodes and releases render resources owned by this
+## loader after all asynchronous work has completed. Map refreshes retain these
+## caches; only scene shutdown destroys them.
+func _release_runtime_caches_for_shutdown() -> void:
+	_free_detached_node_cache(_m2_scene_cache)
+	_free_detached_node_cache(_m2_animated_scene_cache)
+	_free_detached_node_cache(_wmo_prototype_cache)
+	_m2_mesh_cache.clear()
+	_m2_static_animation_cache.clear()
+	_m2_missing_cache.clear()
+	_wmo_render_cache.clear()
+	_wmo_scene_resource_cache.clear()
+	_wmo_render_missing_cache.clear()
+	_wmo_scene_cache_missing.clear()
+	_wmo_missing_cache.clear()
+	_shared_tex_cache.clear()
+
+
+func _free_detached_node_cache(node_cache: Dictionary) -> void:
+	for cached_value in node_cache.values():
+		if not (cached_value is Node):
+			continue
+		var cached_node := cached_value as Node
+		if not is_instance_valid(cached_node):
+			continue
+		if cached_node.is_inside_tree():
+			cached_node.queue_free()
+		else:
+			cached_node.free()
+	node_cache.clear()
 
 
 func _apply_quality_preset() -> void:
@@ -2781,15 +2814,27 @@ func _clear_streamed_world() -> void:
 				_free_render_instance(chunk_rid)
 		var tile_root: Node = state.get("root", null)
 		if tile_root:
-			tile_root.queue_free()
+			_queue_free_streamed_node(tile_root)
 
 	_tile_states.clear()
 	_clear_tile_mesh_cache()
 	_clear_quality_terrain_mesh_cache()
 	_clear_wmo_registry()
-	_ensure_world_wmo_root()
-	if enable_wmo:
-		_place_global_wmo()
+	if not _shutting_down:
+		_ensure_world_wmo_root()
+		if enable_wmo:
+			_place_global_wmo()
+
+
+## During world shutdown, parented nodes are recursively owned by the world
+## root. Queueing them separately from `_exit_tree()` can detach them from that
+## deletion and leave empty Node objects alive at engine teardown.
+func _queue_free_streamed_node(node: Node) -> void:
+	if node == null or not is_instance_valid(node):
+		return
+	if _shutting_down and node.is_inside_tree():
+		return
+	node.queue_free()
 
 
 func _reset_terrain_root_children() -> void:
@@ -3889,10 +3934,10 @@ func _clear_wmo_registry() -> void:
 		var entry: Dictionary = entry_variant
 		var node: Node = entry.get("node", null)
 		if node and is_instance_valid(node):
-			node.queue_free()
+			_queue_free_streamed_node(node)
 	_wmo_registry.clear()
 	if _world_wmo_root and is_instance_valid(_world_wmo_root):
-		_world_wmo_root.queue_free()
+		_queue_free_streamed_node(_world_wmo_root)
 	_world_wmo_root = null
 
 
@@ -4458,7 +4503,7 @@ func _cancel_m2_build_job(key: String) -> void:
 	var job: Dictionary = _m2_build_jobs[key]
 	var root: Node = job.get("root", null)
 	if root != null and is_instance_valid(root):
-		root.queue_free()
+		_queue_free_streamed_node(root)
 	_m2_build_jobs.erase(key)
 
 

src/tools/verify_render_runtime_cache_shutdown.gd

@@ -0,0 +1,77 @@
+extends SceneTree
+
+const STREAMING_WORLD_LOADER := preload("res://src/scenes/streaming/streaming_world_loader.gd")
+const ADT_BUILDER := preload("res://addons/mpq_extractor/loaders/adt_builder.gd")
+
+var _failures := 0
+
+
+func _initialize() -> void:
+	_verify_empty_water_root_ownership()
+	_verify_runtime_cache_ownership()
+
+	if _failures > 0:
+		push_error("Render runtime cache shutdown verification failed: %d issue(s)" % _failures)
+		quit(1)
+		return
+	print("Render runtime cache shutdown verification passed.")
+	quit(0)
+
+
+func _verify_empty_water_root_ownership() -> void:
+	var node_count_before := int(Performance.get_monitor(Performance.OBJECT_NODE_COUNT))
+	var empty_water_root: Node3D = ADT_BUILDER.build_tile_water_scene({"chunks": []}, Vector3.ZERO)
+	var node_count_after := int(Performance.get_monitor(Performance.OBJECT_NODE_COUNT))
+	_expect(empty_water_root == null, "empty ADT liquid payload should not produce a water root")
+	_expect(node_count_after == node_count_before, "empty ADT liquid payload should release its temporary water root")
+
+
+func _verify_runtime_cache_ownership() -> void:
+	var loader: Node = STREAMING_WORLD_LOADER.new()
+	var static_m2_prototype := Node3D.new()
+	var animated_m2_prototype := Node3D.new()
+	var wmo_prototype := Node3D.new()
+
+	loader.set("_m2_scene_cache", {"static": static_m2_prototype})
+	loader.set("_m2_animated_scene_cache", {"animated": animated_m2_prototype})
+	loader.set("_wmo_prototype_cache", {"wmo": wmo_prototype})
+	loader.set("_m2_mesh_cache", {"mesh": ArrayMesh.new()})
+	loader.set("_m2_static_animation_cache", {"static": true})
+	loader.set("_m2_missing_cache", {"missing": true})
+	loader.set("_wmo_render_cache", {"render": Resource.new()})
+	loader.set("_wmo_scene_resource_cache", {"scene": PackedScene.new()})
+	loader.set("_wmo_render_missing_cache", {"missing": true})
+	loader.set("_wmo_scene_cache_missing", {"missing": true})
+	loader.set("_wmo_missing_cache", {"missing": true})
+	loader.set("_shared_tex_cache", {"texture": ImageTexture.new()})
+
+	loader.call("_release_runtime_caches_for_shutdown")
+
+	_expect(not is_instance_valid(static_m2_prototype), "static M2 prototype should be freed")
+	_expect(not is_instance_valid(animated_m2_prototype), "animated M2 prototype should be freed")
+	_expect(not is_instance_valid(wmo_prototype), "WMO prototype should be freed")
+	for cache_name in [
+		"_m2_scene_cache",
+		"_m2_animated_scene_cache",
+		"_wmo_prototype_cache",
+		"_m2_mesh_cache",
+		"_m2_static_animation_cache",
+		"_m2_missing_cache",
+		"_wmo_render_cache",
+		"_wmo_scene_resource_cache",
+		"_wmo_render_missing_cache",
+		"_wmo_scene_cache_missing",
+		"_wmo_missing_cache",
+		"_shared_tex_cache",
+	]:
+		var cache: Dictionary = loader.get(cache_name)
+		_expect(cache.is_empty(), "%s should be empty after shutdown" % cache_name)
+
+	loader.free()
+
+
+func _expect(condition: bool, message: String) -> void:
+	if condition:
+		return
+	_failures += 1
+	push_error(message)