feat: startup environment check + self-heal (v1.3)

- env_check(): verifies daemon/pineapd/UCI/monitors/recon DB, auto-fixes
  fixable issues and re-verifies; forces runtime SSID-pool broadcast off to
  match the UI (kills the 'pool on but UI shows off' gap)
- server.py --env-check CLI; payload.sh runs it verbosely before starting,
  aborts on core failure
- serve() runs the check at every startup (boot + procd respawn)
- /api/health exposes env report + pool_runtime; /api/recon/status exposes
  wlan0_pinned (2.4GHz under-sampling warning); recon page warns when a
  radio0 AP pins wlan0mon
- recon start failures now include the daemon reason in the UI error
- shared stabilization refactor (_stabilize_uci/PINEAPD_SAFE_UCI/_raise_monitors)
- tests: test_env_check.py (18) + health/recon updates

payload/user/remote_access/pager-webui/_hak5_manifest.json

@@ -8,7 +8,7 @@
   "title": "Mark VIII",
   "author": "c4ch3c4d3",
   "description": "Mark VII-style web management UI for the WiFi Pineapple Pager",
-  "version": "1.2",
+  "version": "1.3",
   "category": "remote_access",
   "tags": ["remote-access", "web-interface", "device-management", "pineap"],
   "firmware": "Pineapple Pager 24.10.1"