feat(admin): ask the panel to restart, from verdande's own settings

A container cannot replace its own image from the inside, so "update" is really
"ask whoever owns the container to recreate it" — Yggdrasil pulls `:latest` on the
way, which is what makes a restart an update at all. This removes the second
browser tab, not the panel's authority: the panel still does the work and still
records who asked.

Three settings, needed together, and the page names whichever are missing — an
operator reading "not configured" should not have to go and find out which of
three. The token is never sent to a browser; the page is told only whether it is
set.

Answers 202 rather than waiting. The panel stops this container as part of
answering, so the reply may never arrive, and a request cut off mid-flight is the
successful case wearing a failure's clothes. The interface believes neither answer
and polls /healthz until it responds.

Administrators only, and sessions only. A leaked API token that could restart the
server is a denial of service in one request.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

web/src/lib/locales/da.js

@@ -635,5 +635,16 @@ export const da = {
 	'passkey.signingIn': 'Venter på enheden…',
 
 	'passkey.unavailable':
-		'Passkeys kan ikke bruges her — enten understøtter browseren dem ikke, eller også er serverens adresse en IP frem for et domænenavn, hvilket ingen authenticator accepterer.'
+		'Passkeys kan ikke bruges her — enten understøtter browseren dem ikke, eller også er serverens adresse en IP frem for et domænenavn, hvilket ingen authenticator accepterer.',
+
+	// --- restarting from the interface ---------------------------------------------
+	'update.restart': 'Genstart og hent nyeste version',
+	'update.restarting': 'Genstarter…',
+	'update.restartQuestion':
+		'Genstart nu? Serveren er nede i omkring et halvt minut, og henter den nyeste version på vejen op.',
+	'update.asking': 'Beder panelet om at genstarte…',
+	'update.waiting': 'Venter på at serveren kommer op igen…',
+	'update.stillDown': 'Serveren er ikke kommet op endnu. Kig i panelet.',
+	'update.notConfigured':
+		'Denne instans kan ikke genstarte sig selv: {missing} er ikke sat. En container kan ikke udskifte sit eget image — panelet gør arbejdet, og det her er kun måden at bede om det.'
 };