feat(observability): add phase9 health, readiness, metrics, request tracing, and simulator ops checks

Backend/public/mobile-sim.html

@@ -705,6 +705,46 @@
         }
       });
 
+      const opsPanel = document.createElement('section');
+      opsPanel.className = 'panel';
+      opsPanel.style.marginTop = '16px';
+      opsPanel.innerHTML = `
+        <h2>Ops Checks</h2>
+        <div class="row">
+          <button id="checkLiveBtn" class="alt">GET /ops/live</button>
+          <button id="checkReadyBtn" class="alt">GET /ops/ready</button>
+        </div>
+        <button id="checkMetricsBtn" class="alt">GET /ops/metrics</button>
+      `;
+      document.querySelector('.page').appendChild(opsPanel);
+
+      $('checkLiveBtn').addEventListener('click', async () => {
+        try {
+          const payload = await authFetch('/ops/live');
+          log('ops live', payload);
+        } catch (error) {
+          log('ops live failed', { error: error.message });
+        }
+      });
+
+      $('checkReadyBtn').addEventListener('click', async () => {
+        try {
+          const payload = await authFetch('/ops/ready');
+          log('ops ready', payload);
+        } catch (error) {
+          log('ops ready failed', { error: error.message });
+        }
+      });
+
+      $('checkMetricsBtn').addEventListener('click', async () => {
+        try {
+          const payload = await authFetch('/ops/metrics');
+          log('ops metrics', payload);
+        } catch (error) {
+          log('ops metrics failed', { error: error.message });
+        }
+      });
+
       render();
     </script>
   </body>