feat: 增强 provider query 端点选择逻辑，支持 openai:responses 格式与 key 级 api_formats 过滤

- provider_query_selected_fetch_endpoints 支持按 key.api_formats 过滤可用端点
- 端点选择增加 endpoint_supports_rust_models_fetch 检查
- 支持优先级列表之外的自定义 api_format 端点
- 新增 openai:responses 端点的 provider query 集成测试
- 各 crate 补充缺失的 tracing instrument 和小修正
- 前端 Pool 管理页面补充状态逻辑

apps/aether-gateway/src/tests/architecture/admin_system.rs

@@ -146,7 +146,8 @@ fn admin_system_and_endpoint_roots_stay_thin() {
         ),
         "handlers/admin/endpoint/routes.rs should dispatch provider endpoint CRUD directly to provider::endpoints_admin"
     );
-    for path in ["apps/aether-gateway/src/handlers/admin/endpoint/keys.rs"] {
+    {
+        let path = "apps/aether-gateway/src/handlers/admin/endpoint/keys.rs";
         assert!(
             !workspace_file_exists(path),
             "{path} should be deleted once endpoint root dispatches directly to provider-owned handlers"