feat(extension): update devices UI for new auth model

- Show revoked devices in collapsible section with strikethrough styling
- Fetch revoked.json via new list_revoked message + router case
- Registration flow uses register_device WASM API (private keys internal)
- Display revoked_by and timestamp for each revoked entry
- Update setup wizard to use new register_device API

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

extension/src/service-worker/router/popup-only.ts

@@ -346,6 +346,12 @@ export async function handle(
       return { ok: true, data: { devices: list } };
     }
 
+    case 'list_revoked': {
+      if (!state.gitHost) return { ok: false, error: 'vault_locked' };
+      const revoked = await devices.readRevoked(state.gitHost);
+      return { ok: true, data: { revoked } };
+    }
+
     case 'add_device': {
       if (!state.gitHost) return { ok: false, error: 'vault_locked' };
       const device = {