show server diagnostics in client

src/App.svelte

@@ -2,6 +2,7 @@
   let serverAddress = 'http://127.0.0.1:8787';
   let connectionState = 'OFFLINE';
   let serverVersion = '—';
+  let diagnostics: { status: string; database: string; twitch_identity_count: number; unseen_notification_count: number; realtime: string } | undefined;
   let activeView = 'Live dashboard';
   let sessionToken = '';
   let authenticated = false;
@@ -92,6 +93,7 @@
       connectionState = 'CONNECTED';
       await loadActivity();
       await loadNotifications();
+      await loadDiagnostics();
       await loadStreamInfo();
       connectRealtime();
       if (!mustReplaceCredentials) password = '';
@@ -141,6 +143,7 @@
     oauthLink = '';
     notifications = [];
     showNotifications = false;
+    diagnostics = undefined;
   }
 
   function connectRealtime() {
@@ -199,6 +202,18 @@
     }
   }
 
+  async function loadDiagnostics() {
+    try {
+      const response = await fetch(`${serverAddress}/api/v1/server/diagnostics`, {
+        headers: { authorization: `Bearer ${sessionToken}` },
+      });
+      if (!response.ok) return;
+      diagnostics = await response.json();
+    } catch {
+      diagnostics = undefined;
+    }
+  }
+
   async function markNotificationSeen(notificationId: string) {
     const response = await fetch(`${serverAddress}/api/v1/admin/notifications/${notificationId}/seen`, {
       method: 'POST',
@@ -412,7 +427,7 @@
           <div class="empty-row">Sign in as administrator to connect accounts.</div>
         {/if}
       </div>
-      <div class="side-section side-footer"><div class="micro">REALTIME</div><div class="mono">{realtimeState}</div><div class="micro version-label">SERVER VERSION</div><div class="mono">{serverVersion}</div></div>
+      <div class="side-section side-footer"><div class="micro">REALTIME</div><div class="mono">{realtimeState}</div>{#if diagnostics}<div class="micro version-label">DATABASE</div><div class="mono">{diagnostics.database.toUpperCase()}</div><div class="micro version-label">TWITCH IDENTITIES</div><div class="mono">{diagnostics.twitch_identity_count}</div>{/if}<div class="micro version-label">SERVER VERSION</div><div class="mono">{serverVersion}</div></div>
     </aside>
 
     <section class="content-area">