feat: add device passkeys for operator access (Closes #485)

frontend/index.html

@@ -36,6 +36,7 @@
       <button id="close-active-devices" type="button" aria-label="Close active devices">Close</button>
     </div>
     <div id="active-devices-status" class="small" role="status" aria-live="polite"></div>
+    <button id="enroll-passkey" type="button">Add a passkey for this device</button>
     <div id="active-devices-list" class="active-devices-list"></div>
   </section>
 </div>