Force HTTPS from the admin, with a probe before and after

System > HTTPS and cms:https switch the redirect lines in public/.htaccess
only when the site answers over HTTPS, and take them back on a loop. HSTS
is a separate second switch. The redirect block moves before the front
controller rules, where it never reached pages, and .well-known is no
longer denied, so the origin probe works on Apache. The Git updater keeps
switched-on lines like the archive update.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

public/assets/admin.css

@@ -697,6 +697,8 @@ details.card > summary:hover { background: #fafbf8 }
 .origin-row { display: flex; flex-wrap: wrap; gap: 8px }
 .origin-row input { flex: 1 1 240px; width: auto; box-sizing: border-box; min-height: 40px; height: 40px }
 .card-body .origin-row .secondary { margin: 0 }
+.https-actions { display: flex; flex-wrap: wrap; gap: 8px; margin-top: 8px }
+.card-body .https-actions .secondary { margin: 0 }
 .origin-form .check-label { margin-top: 10px }
 .link-button { border: 0; background: none; padding: 0; min-height: 0; font: inherit; color: var(--accent); text-decoration: underline; cursor: pointer }
 .check-list { list-style: none; margin: 14px 0 0; padding: 0; display: grid; gap: 10px; font-size: 13px; line-height: 1.55 }