Improve Feishu permission checks and OpenVPN auth result page

frontend/src/locales/en-US.json

@@ -575,8 +575,9 @@
   },
   "identity": {
     "tab": "Feishu identity", "title": "Built-in Feishu identity service", "description": "Issue OIDC identities for VPN using your existing HTTPS domain. Feishu app credentials stay upstream; this platform creates separate VPN client credentials.",
-    "guideTitle": "Configure your Feishu app", "guideApp": "In Feishu Open Platform → Enterprise apps, open your app. Copy the App ID and App Secret from Credentials & Basic Information into the fields below. Use enterprise app credentials.", "guidePermission": "For automatic tenant lookup, request enterprise information read access (search for tenant:tenant:readonly or 'get enterprise information'; use the actual name shown by Feishu). For browser login, request the basic user information permission contact:user.base:readonly (use Feishu's actual console label).", "guidePublish": "Publish or enable the new app version, complete administrator review if required, and add VPN users to the app's availability scope. Creating the app or adding a permission alone does not activate it.", "guideCallback": "In Security Settings → Redirect URLs, add this exact Feishu sign-in callback:", "guideCallbackPending": "Configure the HTTPS domain under Public Gateway first to see the callback URL.", "guideVerify": "Save and enable the identity service, then sync its public routes. Configure and start an OIDC OpenVPN tunnel, verify openvpn-auth-oauth2 is installed, sync the routes again, and test with a user in the app's availability scope.", "guideManual": "If automatic lookup fails, enter a tenant_key verified from user information in the same enterprise. The Feishu error code appears below the field; retry after changing credentials or permissions.", "guideScope": "Finding tenant_key only proves the enterprise information API works; it does not confirm Feishu browser sign-in or VPN access. Browser login also needs the basic user information permission contact:user.base:readonly, the callback URL, app publication, and user availability. VPN also needs a tunnel and auth component. The Feishu callback differs from the VPN callback.",
-    "appId": "Feishu App ID", "appSecret": "Feishu App Secret", "secretPlaceholder": "Leave blank to retain the secret; use a rotated secret for new setup", "tenant": "Allowed Feishu tenant_key", "tenantPlaceholder": "Fetch automatically or enter manually", "fetchTenant": "Fetch tenant ID", "fetchingTenant": "Requesting Feishu ({seconds}s)…", "tenantFetched": "Feishu tenant ID retrieved", "tenantFailed": "Could not fetch Feishu tenant", "tenantNotEnabled": "Tenant ID is set; enable the identity service and finish the callback, app publication, and tunnel configuration.", "enabled": "Enable built-in issuer", "httpsOnly": "Enter app credentials only through the HTTPS management site. Switch to its secure address.", "openHttps": "Open HTTPS management site",
+    "guideTitle": "Feishu app setup", "guideApp": "Enter the enterprise app ID and secret; enable both permissions below.", "guidePermission": "", "guidePublish": "Publish the app and include VPN users in its availability scope.", "guideCallback": "Security Settings → Redirect URL:", "guideCallbackPending": "Configure an HTTPS domain first.", "guideVerify": "", "guideManual": "", "guideScope": "",
+    "tenantPermission": "tenant:tenant:readonly · enterprise", "userPermission": "contact:user.base:readonly · user", "checking": "Checking", "checked": "Verified", "checkFailed": "Check failed", "checkPending": "Not checked", "checkedByLogin": "Login verified", "loginPending": "Verify on first login",
+    "appId": "Feishu App ID", "appSecret": "Feishu App Secret", "secretPlaceholder": "Leave blank if saved; enter a new secret to rotate", "tenant": "Allowed Feishu tenant_key", "tenantPlaceholder": "Fetched automatically or enter manually", "fetchTenant": "Check again", "fetchingTenant": "Checking ({seconds}s)…", "tenantFetched": "Enterprise permission verified", "tenantFailed": "Enterprise permission check failed", "tenantNotEnabled": "", "enabled": "Enable built-in issuer", "httpsOnly": "Use HTTPS to enter app credentials.", "openHttps": "Open HTTPS management site",
     "httpsRequired": "Configure and activate your public HTTPS site and certificate first.", "gatewayPending": "The identity provider is saved but Nginx does not yet route /id/; sync the gateway.",
     "addresses": "Addresses and client credentials", "issuer": "OIDC issuer", "feishuCallback": "Callback registered in Feishu", "vpnCallback": "VPN client callback", "clientId": "VPN Client ID",
     "oneTimeSecret": "New VPN Client Secret is displayed only once. Store it safely; rotation of active tunnel credentials requires separate planning.", "routeHint": "Sync identity routes first. After starting the one OpenVPN OIDC tunnel using this domain, sync again to route /oauth2/ to its local auth component.",