feat: federation instance list and api/healthz improvements

src/lib/components/Navbar.svelte

@@ -48,6 +48,13 @@
 					{t('navigation.create')}
 				</button>
 
+				<button
+					on:click={() => goto('/instance')}
+					class={isActive('/instance') ? 'text-violet-400' : 'cursor-pointer'}
+				>
+					{t('navigation.instance')}
+				</button>
+
 				<button
 					on:click={() => goto('/event')}
 					class={isActive('/event') ? 'text-violet-400' : 'cursor-pointer'}