feat(quota): add quota page and update i18n

src/i18n/locales/en.json

@@ -90,6 +90,7 @@
     "ai_providers": "AI Providers",
     "auth_files": "Auth Files",
     "oauth": "OAuth Login",
+    "quota_management": "Quota Management",
     "usage_stats": "Usage Statistics",
     "config_management": "Config Management",
     "logs": "Logs Viewer",
@@ -704,6 +705,11 @@
     "search_prev": "Previous",
     "search_next": "Next"
   },
+  "quota_management": {
+    "title": "Quota Management",
+    "description": "Monitor OAuth quota status for Antigravity, Codex, and Gemini CLI credentials.",
+    "refresh_files": "Refresh auth files"
+  },
   "system_info": {
     "title": "Management Center Info",
     "connection_status_title": "Connection Status",

src/i18n/locales/zh-CN.json

@@ -90,6 +90,7 @@
     "ai_providers": "AI 提供商",
     "auth_files": "认证文件",
     "oauth": "OAuth 登录",
+    "quota_management": "配额管理",
     "usage_stats": "使用统计",
     "config_management": "配置管理",
     "logs": "日志查看",
@@ -704,6 +705,11 @@
     "search_prev": "上一个",
     "search_next": "下一个"
   },
+  "quota_management": {
+    "title": "配额管理",
+    "description": "集中查看 OAuth 额度与剩余情况",
+    "refresh_files": "刷新认证文件"
+  },
   "system_info": {
     "title": "管理中心信息",
     "connection_status_title": "连接状态",