fix(notifications): retarget bell dropdown footer to /chronik

The "Alle anzeigen" link at the bottom of the notification dropdown now
points to /chronik with the new "Zur Chronik →" label key, matching the
unified activity page introduced in #285.

Part of #285.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

frontend/src/lib/components/NotificationDropdown.svelte

@@ -128,11 +128,11 @@ let { notifications, onMarkRead, onMarkAllRead, onClose }: Props = $props();
 
 	<div class="border-t border-line px-4 py-2">
 		<a
-			href="/notifications"
+			href="/chronik"
 			onclick={onClose}
 			class="text-xs font-medium text-ink-2 transition-colors hover:text-ink"
 		>
-			{m.notification_view_all()}
+			{m.chronik_view_all()}
 		</a>
 	</div>
 </div>