refactor: 继续拆分大型模块并增强模块注册健壮性

后端:
- chat_handler_base 错误处理函数提取到 chat_error_utils 子模块
- CLI mixin 引入 CliHandlerProtocol 协议类改善类型标注
- aware_scheduler 拆分为 _candidate_builder 和 _candidate_sorter 子模块
- usage recording 拆分为 _billing_integration 和 _recording_helpers 子模块
- ModuleRegistry 添加循环依赖检测，将写操作从查询方法分离到 reconcile_module_state
- 修正 plugin manager 入度注释

前端:
- 路由守卫逻辑拆分为独立 guards 模块
- ProviderManagement 拆分为 TableHeader/TableRow/BalanceCell/MobileCard 子组件
- SystemSettings 拆分为多个 Section 子组件和 composables
- 提取 useEndpointStatus/useProviderBalance/useProviderFilters composables

测试适配重构后的子模块结构

tests/services/test_aware_scheduler_model_support.py

@@ -22,7 +22,7 @@ class TestCheckModelSupportForGlobalModel:
     """测试 _check_model_support_for_global_model 方法"""
 
     @pytest.mark.asyncio
-    async def test_provider_without_model_should_return_false(self):
+    async def test_provider_without_model_should_return_false(self) -> None:
         """Provider 没有配置对应的 Model 时应该返回 False"""
         scheduler = CacheAwareScheduler()
 
@@ -45,7 +45,7 @@ class TestCheckModelSupportForGlobalModel:
 
         with patch("sqlalchemy.inspect", return_value=mock_inspect):
             is_supported, skip_reason, caps, provider_model_names = (
-                await scheduler._check_model_support_for_global_model(
+                await scheduler._candidate_builder._check_model_support_for_global_model(
                     db=db,
                     provider=provider,
                     global_model=global_model,
@@ -59,7 +59,7 @@ class TestCheckModelSupportForGlobalModel:
         assert provider_model_names is None
 
     @pytest.mark.asyncio
-    async def test_provider_with_different_model_should_return_false(self):
+    async def test_provider_with_different_model_should_return_false(self) -> None:
         """Provider 配置了其他模型但没有目标模型时应该返回 False"""
         scheduler = CacheAwareScheduler()
 
@@ -93,7 +93,7 @@ class TestCheckModelSupportForGlobalModel:
 
         with patch("sqlalchemy.inspect", return_value=mock_inspect):
             is_supported, skip_reason, caps, provider_model_names = (
-                await scheduler._check_model_support_for_global_model(
+                await scheduler._candidate_builder._check_model_support_for_global_model(
                     db=db,
                     provider=provider,
                     global_model=global_model,
@@ -105,7 +105,7 @@ class TestCheckModelSupportForGlobalModel:
         assert skip_reason == "Provider 未实现此模型"
 
     @pytest.mark.asyncio
-    async def test_provider_with_matching_model_should_return_true(self):
+    async def test_provider_with_matching_model_should_return_true(self) -> None:
         """Provider 配置了目标模型时应该返回 True"""
         scheduler = CacheAwareScheduler()
 
@@ -136,7 +136,7 @@ class TestCheckModelSupportForGlobalModel:
 
         with patch("sqlalchemy.inspect", return_value=mock_inspect):
             is_supported, skip_reason, caps, provider_model_names = (
-                await scheduler._check_model_support_for_global_model(
+                await scheduler._candidate_builder._check_model_support_for_global_model(
                     db=db,
                     provider=provider,
                     global_model=global_model,
@@ -150,7 +150,7 @@ class TestCheckModelSupportForGlobalModel:
         assert provider_model_names == {"claude-3-haiku-20240307"}
 
     @pytest.mark.asyncio
-    async def test_provider_with_inactive_model_should_return_false(self):
+    async def test_provider_with_inactive_model_should_return_false(self) -> None:
         """Provider 的模型未激活时应该返回 False"""
         scheduler = CacheAwareScheduler()
 
@@ -179,7 +179,7 @@ class TestCheckModelSupportForGlobalModel:
 
         with patch("sqlalchemy.inspect", return_value=mock_inspect):
             is_supported, skip_reason, caps, provider_model_names = (
-                await scheduler._check_model_support_for_global_model(
+                await scheduler._candidate_builder._check_model_support_for_global_model(
                     db=db,
                     provider=provider,
                     global_model=global_model,