Telegram Mini App creates a new WebView on each open, clearing
sessionStorage. Combined with 24h auth_date validation on backend,
returning users couldn't re-authenticate after closing the app.
- Move refresh token to localStorage for persistence across sessions
- Keep access token in sessionStorage (short-lived, OK to lose)
- Fix auth store initialize() to recover when access token is missing
but refresh token exists in localStorage
- Remove separate mountThemeParams() call to fix ConcurrentCallError
(mountMiniApp() handles it internally in SDK v3)
- Update token migration logic for new storage strategy
- Skip token refresh/Bearer header for auth endpoints in request interceptor
- Wait for auth store initialization before attempting Telegram login
- Clear stale session tokens when init data changes (WebView persistence)
- Show backend error details instead of generic messages
