security: Sentinel 路由鉴权 + API Key CSRF + SSRF 防护

修复:
- Sentinel 路由 require_auth=False → True (严重: 未认证可访问)
- API Key 创建/删除加 csrf_protect=True
- SSRF 防护: 测试连接仅允许 http/https scheme
- 插件网络鉴权: 已加载插件自动放行 (不再要求 plugin.network.access)
- Sentinel 权限列表补充 plugin.network.access

Co-Authored-By: Claude <noreply@anthropic.com>

services/web_panel/routes/apikeys.py

@@ -171,6 +171,6 @@ def setup_routes(app, prefix=""):
             return web.json_response({"error": str(e)}, status=500)
 
     app.router.add_get(f"{prefix}/api/apikeys", panel_auth(list_keys))
-    app.router.add_post(f"{prefix}/api/apikeys", panel_auth(create_key))
-    app.router.add_delete(f"{prefix}/api/apikeys", panel_auth(delete_key))
+    app.router.add_post(f"{prefix}/api/apikeys", panel_auth(create_key, csrf_protect=True))
+    app.router.add_delete(f"{prefix}/api/apikeys", panel_auth(delete_key, csrf_protect=True))
     logger.info(f"🔑 API Key 管理路由已注册 ({prefix}/api/apikeys)")