R-718: the close-sign-up and setup-gate cards say the app restarts once

Where the app has its own switch (after_setup.env), both presses restart
it; the cards now say so (app_info.restarts_once, hu+en). Two parity
cases born with the line.

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_0159rPz1ZhFKsS53msqPYxtS

controller/internal/i18n/locales/en.json

@@ -2563,6 +2563,7 @@
   "app_info.close_signup_btn": "Close sign-up now",
   "app_info.signup_native_failed": "The app's own sign-up switch could not be closed. The address block still protects it.",
   "app_info.signup_window_restart": "The app restarts for this, and once more when the 15 minutes end.",
+  "app_info.restarts_once": "For this the app restarts once and is briefly unavailable meanwhile.",
   "err.setup_gate.close_signup_not_offered": "There is nothing to close on this app.",
   "backups_offsite.offer_text": "Some apps have no off-site copy. Turn it on for all of them?",
   "backups_offsite.offer_all": "Yes, all of them",