Anonymous users seeing the 403 page now get an inline login form
with username, password, and submit button. After login, redirects
back to the page they were trying to access.
Compact form centered with tw-max-w-sm, includes CSRF token and
redirect_to hidden field pointing to CurrentURL.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>