refactor: 全面重构核心架构，消除反复修改的根因

- 删除 ValidationQueue 双轨持久化队列，替换为纯内存 AsyncWorkerPool
- 引入统一后台任务框架 JobExecutor（Job/CrawlJob/ValidateAllJob）
- 新增 PluginRunner 统一插件执行（超时、重试、健康检查、统计）
- 重构 SchedulerService 职责收敛为仅定时触发 ValidateAllJob
- 使用 AsyncExitStack 重构 lifespan，安全管理长生命周期资源
- 路由层瘦身 50%+，业务异常上抛由全局中间件统一处理
- 实现设置全热更新（WorkerPool 并发、Validator 超时即时生效）
- 前端 Store 强制写后重新拉取，消除乐观更新数据不同步
- 删除 queue.py / task_repo.py / task_service.py
- 新增 execution 单元测试，全部 85 个测试通过

tests/conftest.py

@@ -7,6 +7,17 @@ from httpx import AsyncClient, ASGITransport
 
 from app.api import create_app
 from app.core.db import init_db, get_db
+from app.core.plugin_system.registry import registry
+from app.plugins import (
+    Fate0Plugin,
+    ProxyListDownloadPlugin,
+    Ip3366Plugin,
+    Ip89Plugin,
+    KuaiDaiLiPlugin,
+    SpeedXPlugin,
+    YunDaiLiPlugin,
+    ProxyScrapePlugin,
+)
 from app.repositories.proxy_repo import ProxyRepository
 from app.models.domain import ProxyRaw
 
@@ -14,23 +25,32 @@ from app.models.domain import ProxyRaw
 @pytest_asyncio.fixture(scope="function")
 async def app():
     """创建应用实例"""
-    # 初始化测试数据库并清空历史数据，避免任务残留或设置状态导致 drain() 卡住
+    # 初始化测试数据库并清空历史数据
     await init_db()
     async with get_db() as db:
-        await db.execute("DELETE FROM validation_tasks")
         await db.execute("DELETE FROM proxies")
         await db.execute("DELETE FROM settings")
         await db.commit()
     
-    # 清理全局内存状态，防止跨测试污染
-    from app.services.task_service import task_service
-    task_service._tasks.clear()
+    # 清理并重新注册插件，防止跨测试污染
+    registry.clear()
+    for plugin_cls in [
+        Fate0Plugin,
+        ProxyListDownloadPlugin,
+        Ip3366Plugin,
+        Ip89Plugin,
+        KuaiDaiLiPlugin,
+        SpeedXPlugin,
+        YunDaiLiPlugin,
+        ProxyScrapePlugin,
+    ]:
+        registry.register(plugin_cls)
     
     test_app = create_app()
     async with test_app.router.lifespan_context(test_app):
         yield test_app
     
-    # 给 aiosqlite / aiohttp 后台线程留出收尾时间，降低 Event loop closed 警告概率
+    # 给 aiosqlite / aiohttp 后台线程留出收尾时间
     await asyncio.sleep(0.1)
 
 
@@ -71,18 +91,19 @@ async def mock_external_requests(monkeypatch):
     1. 插件爬取返回固定测试代理，避免真实 HTTP 请求
     2. 代理验证瞬间成功，避免连接超时等待
     """
-    from app.services.plugin_service import PluginService
+    from app.services.plugin_runner import PluginRunner
     from app.services.validator_service import ValidatorService
 
-    async def _mock_run_plugin(self, plugin_id: str):
-        return [ProxyRaw("192.168.100.10", 8080, "http")]
-
-    async def _mock_run_all_plugins(self):
-        return [ProxyRaw("192.168.100.10", 8080, "http")]
+    async def _mock_run(self, plugin):
+        from app.models.domain import CrawlResult
+        return CrawlResult(
+            plugin_name=plugin.name,
+            proxies=[ProxyRaw("192.168.100.10", 8080, "http")],
+            success_count=1,
+        )
 
     async def _mock_validate(self, ip: str, port: int, protocol: str = "http"):
         return True, 1.23
 
-    monkeypatch.setattr(PluginService, "run_plugin", _mock_run_plugin)
-    monkeypatch.setattr(PluginService, "run_all_plugins", _mock_run_all_plugins)
+    monkeypatch.setattr(PluginRunner, "run", _mock_run)
     monkeypatch.setattr(ValidatorService, "validate", _mock_validate)

tests/integration/test_plugins_api.py

@@ -69,7 +69,8 @@ class TestPluginsAPI:
         
         plugin_id = plugins[0]["id"]
         response = await client.put(f"/api/plugins/{plugin_id}/toggle", json={})
-        assert response.status_code == 400
+        # Pydantic 验证缺失必填字段返回 422
+        assert response.status_code == 422
 
     @pytest.mark.asyncio
     async def test_toggle_nonexistent_plugin(self, client):