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/package-lock.json

@@ -1,12 +1,12 @@
 {
   "name": "mikrotik-manager-backend",
-  "version": "0.16.1-beta",
+  "version": "0.16.2-beta",
   "lockfileVersion": 3,
   "requires": true,
   "packages": {
     "": {
       "name": "mikrotik-manager-backend",
-      "version": "0.16.1-beta",
+      "version": "0.16.2-beta",
       "dependencies": {
         "@influxdata/influxdb-client": "^1.33.2",
         "@influxdata/influxdb-client-apis": "^1.35.0",