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/api.js

@@ -199,6 +199,8 @@ export const api = {
 	deleteUser: (id) => del(`/users/${id}`),
 	revokeInvite: (id) => del(`/invites/${id}`),
 	listErrors: () => get('/errors'),
+	panelStatus: () => get('/panel'),
+	restartFromPanel: () => post('/panel/restart'),
 
 	// The nightly backup, which ran since the beginning with nothing to show it.
 	// The OAuth client itself, which is the instance's registration with Google

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.'
 };

web/src/lib/locales/en.js

@@ -630,5 +630,16 @@ export const en = {
 	'passkey.signingIn': 'Waiting for the device…',
 
 	'passkey.unavailable':
-		'Passkeys cannot be used here — either this browser does not support them, or the server’s address is an IP rather than a domain name, which no authenticator will accept.'
+		'Passkeys cannot be used here — either this browser does not support them, or the server’s address is an IP rather than a domain name, which no authenticator will accept.',
+
+	// --- restarting from the interface ---------------------------------------------
+	'update.restart': 'Restart and pull the latest version',
+	'update.restarting': 'Restarting…',
+	'update.restartQuestion':
+		'Restart now? The server is down for about half a minute, and pulls the newest version on the way back up.',
+	'update.asking': 'Asking the panel to restart…',
+	'update.waiting': 'Waiting for the server to come back…',
+	'update.stillDown': 'The server has not come back yet. Have a look in the panel.',
+	'update.notConfigured':
+		'This instance cannot restart itself: {missing} are not set. A container cannot replace its own image — the panel does the work, and this is only the way to ask.'
 };