fix: 修复聊天系统编译错误

- 修复 WebSocketManager/SocketIOClient 函数缩进错误
- 重命名 is_connected() 避免与 Object 基类冲突
- 修复 tscn 文件多余前导空格
- 修复测试文件 GUT 断言函数调用
- 添加 GUT 测试框架

addons/gut/lazy_loader.gd

@@ -0,0 +1,39 @@
+@tool
+# ------------------------------------------------------------------------------
+# Static
+# ------------------------------------------------------------------------------
+static var usage_counter = load('res://addons/gut/thing_counter.gd').new()
+static var WarningsManager = load('res://addons/gut/warnings_manager.gd')
+
+static func load_all():
+	for key in usage_counter.things:
+		key.get_loaded()
+
+
+static func print_usage():
+	for key in usage_counter.things:
+		print(key._path, '  (', usage_counter.things[key], ')')
+
+
+static func clear():
+	usage_counter.things.clear()
+
+# ------------------------------------------------------------------------------
+# Class
+# ------------------------------------------------------------------------------
+var _loaded = null
+var _path = null
+
+func _init(path):
+	_path = path
+	usage_counter.add_thing_to_count(self)
+
+
+func get_loaded():
+	if(_loaded == null):
+		_loaded = WarningsManager.load_script_ignoring_all_warnings(_path)
+	usage_counter.add(self)
+	return _loaded
+
+
+