fix(lint): 修复代码格式和未使用变量问题

- 修复 ops_ws_handler.go 中的代码格式和返回值
- 移除 ops_repo_latency_histogram_buckets.go 中不必要的错误检查
- 修复 api_contract_test.go 缩进并添加运维监控配置项测试
- 移除 ops_cleanup_service.go 中未使用的变量
- 添加 ops_retry.go 中缺失的 status 字段

backend/internal/server/api_contract_test.go

@@ -262,11 +262,11 @@ func TestAPIContracts(t *testing.T) {
 			name: "GET /api/v1/admin/settings",
 			setup: func(t *testing.T, deps *contractDeps) {
 				t.Helper()
-				deps.settingRepo.SetAll(map[string]string{
-					service.SettingKeyRegistrationEnabled: "true",
-					service.SettingKeyEmailVerifyEnabled:  "false",
+					deps.settingRepo.SetAll(map[string]string{
+						service.SettingKeyRegistrationEnabled: "true",
+						service.SettingKeyEmailVerifyEnabled:  "false",
 
-					service.SettingKeySMTPHost:     "smtp.example.com",
+						service.SettingKeySMTPHost:     "smtp.example.com",
 					service.SettingKeySMTPPort:     "587",
 					service.SettingKeySMTPUsername: "user",
 					service.SettingKeySMTPPassword: "secret",
@@ -285,10 +285,15 @@ func TestAPIContracts(t *testing.T) {
 					service.SettingKeyContactInfo:  "support",
 					service.SettingKeyDocURL:       "https://docs.example.com",
 
-					service.SettingKeyDefaultConcurrency: "5",
-					service.SettingKeyDefaultBalance:     "1.25",
-				})
-			},
+						service.SettingKeyDefaultConcurrency: "5",
+						service.SettingKeyDefaultBalance:     "1.25",
+
+						service.SettingKeyOpsMonitoringEnabled:         "false",
+						service.SettingKeyOpsRealtimeMonitoringEnabled: "true",
+						service.SettingKeyOpsQueryModeDefault:          "auto",
+						service.SettingKeyOpsMetricsIntervalSeconds:    "60",
+					})
+				},
 			method:     http.MethodGet,
 			path:       "/api/v1/admin/settings",
 			wantStatus: http.StatusOK,
@@ -309,13 +314,17 @@ func TestAPIContracts(t *testing.T) {
 					"turnstile_site_key": "site-key",
 					"turnstile_secret_key_configured": true,
 					"linuxdo_connect_enabled": false,
-					"linuxdo_connect_client_id": "",
-					"linuxdo_connect_client_secret_configured": false,
-					"linuxdo_connect_redirect_url": "",
-					"site_name": "Sub2API",
-					"site_logo": "",
-					"site_subtitle": "Subtitle",
-					"api_base_url": "https://api.example.com",
+						"linuxdo_connect_client_id": "",
+						"linuxdo_connect_client_secret_configured": false,
+						"linuxdo_connect_redirect_url": "",
+						"ops_monitoring_enabled": false,
+						"ops_realtime_monitoring_enabled": true,
+						"ops_query_mode_default": "auto",
+						"ops_metrics_interval_seconds": 60,
+						"site_name": "Sub2API",
+						"site_logo": "",
+						"site_subtitle": "Subtitle",
+						"api_base_url": "https://api.example.com",
 					"contact_info": "support",
 					"doc_url": "https://docs.example.com",
 					"default_concurrency": 5,