实现插件配置持久化与任务队列持久化

插件配置持久化：
- plugin_settings 表新增 config_json 字段，支持存储每个插件的自定义配置
- BaseCrawlerPlugin 新增 default_config 属性和 update_config 方法
- PluginSettingsRepository 新增 get_config / set_config 方法
- PluginService 新增 get_plugin_config 和 update_plugin_config
- api/routes/plugins.py 新增 GET /{id}/config 和 POST /{id}/config 接口
- 前端 Plugins.vue 增加配置编辑对话框，支持动态渲染数字/布尔/字符串类型配置
- ip3366 插件示例化：增加 max_pages 配置项，验证配置生效后会动态更新爬取 URL

任务队列持久化：
- 新建 validation_tasks 表：id, ip, port, protocol, status, result, response_time_ms, created_at, updated_at
- 新建 ValidationTaskRepository，提供 insert_batch / acquire_pending / complete_task / reset_processing 等方法
- ValidationQueue 重构：
  - submit() 时把任务写入数据库并唤醒 Worker
  - Worker 通过 acquire_pending 原子取任务并验证
  - 验证完成后更新任务状态并入库有效代理
  - 启动时自动恢复之前中断的 processing 任务为 pending
  - 支持 drain() 等待所有 pending 完成
- 调度器验证流程同样自动持久化到任务表

其他适配：
- 更新 api/deps.py 和 api/lifespan.py，移除对已删除 settings_service 的残留引用
- 更新前端 pluginService.js 和 api/index.js 增加配置相关 API

api/routes/plugins.py

@@ -2,7 +2,6 @@
 from fastapi import APIRouter, Depends
 from services.plugin_service import PluginService
 from services.scheduler_service import SchedulerService
-from models.schemas import PluginToggleRequest
 from api.deps import get_plugin_service, get_scheduler_service
 from core.log import logger
 
@@ -26,7 +25,7 @@ async def list_plugins(service: PluginService = Depends(get_plugin_service)):
             "plugins": [
                 {
                     "id": p.id,
-                    "name": p.display_name,  # 保持旧版本兼容：name 用于展示
+                    "name": p.display_name,
                     "display_name": p.display_name,
                     "description": p.description,
                     "enabled": p.enabled,
@@ -43,18 +42,47 @@ async def list_plugins(service: PluginService = Depends(get_plugin_service)):
 @router.put("/{plugin_id}/toggle")
 async def toggle_plugin(
     plugin_id: str,
-    request: PluginToggleRequest,
+    request: dict,
     service: PluginService = Depends(get_plugin_service),
 ):
-    success = await service.toggle_plugin(plugin_id, request.enabled)
+    enabled = request.get("enabled")
+    if enabled is None:
+        return error_response("缺少 enabled 参数", 400)
+    success = await service.toggle_plugin(plugin_id, enabled)
     if not success:
         return error_response("插件不存在", 404)
     return success_response(
-        f"插件 {plugin_id} 已{'启用' if request.enabled else '禁用'}",
-        {"plugin_id": plugin_id, "enabled": request.enabled},
+        f"插件 {plugin_id} 已{'启用' if enabled else '禁用'}",
+        {"plugin_id": plugin_id, "enabled": enabled},
     )
 
 
+@router.get("/{plugin_id}/config")
+async def get_plugin_config(
+    plugin_id: str,
+    service: PluginService = Depends(get_plugin_service),
+):
+    config = await service.get_plugin_config(plugin_id)
+    if config is None:
+        return error_response("插件不存在", 404)
+    return success_response("获取插件配置成功", {"plugin_id": plugin_id, "config": config})
+
+
+@router.post("/{plugin_id}/config")
+async def update_plugin_config(
+    plugin_id: str,
+    request: dict,
+    service: PluginService = Depends(get_plugin_service),
+):
+    config = request.get("config", {})
+    if not isinstance(config, dict):
+        return error_response("config 必须是对象", 400)
+    success = await service.update_plugin_config(plugin_id, config)
+    if not success:
+        return error_response("插件不存在或配置无效", 404)
+    return success_response("保存插件配置成功", {"plugin_id": plugin_id, "config": config})
+
+
 @router.post("/{plugin_id}/crawl")
 async def crawl_plugin(
     plugin_id: str,