refactor: centralize MoviePilot server helper

tests/test_system_llm_test.py

@@ -9,14 +9,15 @@ _ORIGINAL_STUBBED_MODULES = {}
 
 
 def _stub_module(name: str, **attrs):
+    """
+    安装临时 stub 模块，并记录原模块用于导入后恢复。
+    """
     if name not in _ORIGINAL_STUBBED_MODULES:
         _ORIGINAL_STUBBED_MODULES[name] = sys.modules.get(name)
-    module = sys.modules.get(name)
-    if module is None:
-        module = ModuleType(name)
-        sys.modules[name] = module
+    module = ModuleType(name)
     for key, value in attrs.items():
         setattr(module, key, value)
+    sys.modules[name] = module
     return module
 
 
@@ -76,7 +77,7 @@ _stub_module("app.helper.mediaserver", MediaServerHelper=_Dummy)
 _stub_module("app.helper.message", MessageHelper=_Dummy)
 _stub_module("app.helper.progress", ProgressHelper=_Dummy)
 _stub_module("app.helper.rule", RuleHelper=_Dummy)
-_stub_module("app.helper.subscribe", SubscribeHelper=_Dummy)
+_stub_module("app.helper.server", MoviePilotServerHelper=_Dummy)
 _stub_module("app.helper.system", SystemHelper=_Dummy)
 _stub_module("app.helper.image", ImageHelper=_Dummy)
 _stub_module("app.scheduler", Scheduler=_Dummy)