feat(ops): operations insights engine + working quick actions; fix global search (v0.16.2-beta)

Global search:
- Clicking/Enter on a client result now opens that client's detail page
  (/clients/<mac>) instead of dumping to the clients list.

Operations dashboard (new backend route /api/operations):
- GET /insights: server-side attention engine (offline, updates, CPU/memory
  pressure, missing backups, recent outages, weak WiFi clients, co-channel
  overlap, high TX retries, error events) + per-device capacity + merged
  activity feed (config changes, audit actions, alerts; login noise filtered).
- POST /backup-all and /sync-all: fleet-wide actions over online devices.
- Quick Actions now execute: Run discovery, Backup all, Sync config, and
  Open terminal (device picker -> live SSH TerminalModal); inline status.
- New cards: Capacity & health meters, Security posture rollup (reuses
  per-device posture, cached), Recent activity feed.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

backend/src/index.ts

@@ -36,6 +36,7 @@ import devicesRoutes, { setPollerService as setDevicesPoller } from './routes/de
 import clientsRoutes, { setPollerService as setClientsPoller } from './routes/clients';
 import eventsRoutes from './routes/events';
 import backupsRoutes from './routes/backups';
+import operationsRoutes from './routes/operations';
 import metricsRoutes from './routes/metrics';
 import topologyRoutes, { setPollerService as setTopologyPoller } from './routes/topology';
 import settingsRoutes from './routes/settings';
@@ -206,6 +207,7 @@ app.use('/api/devices', devicesRoutes);
 app.use('/api/clients', clientsRoutes);
 app.use('/api/events', eventsRoutes);
 app.use('/api/backups', backupsRoutes);
+app.use('/api/operations', operationsRoutes);
 app.use('/api/metrics', metricsRoutes);
 app.use('/api/topology', topologyRoutes);
 app.use('/api/settings', settingsRoutes);