Fix MEDIUM findings from 2026-09-24 maintenance review

- Backend retries DB connection at startup (up to 180s) so host reboots
  no longer crash-loop it; add backend and frontend healthchecks
- Docker log rotation (json-file 10m x 3) on all services
- ntfy alerts use X-Real-IP (set by nginx after real_ip resolution)
  instead of the client-controlled first X-Forwarded-For entry
- Frontend build on Node 24 LTS with package-lock.json + npm ci;
  axios 1.20.0, vite 5.4.21
- README: backup/restore/rollback runbook, real-IP proxy trust notes
- Release-Notes/v1.1.md; version 1.1.0

Co-Authored-By: Claude Opus 5.5 <[email protected]>

frontend/package.json

@@ -1,6 +1,6 @@
 {
   "name": "homeschool-frontend",
-  "version": "1.0.0",
+  "version": "1.1.0",
   "private": true,
   "scripts": {
     "dev": "vite",
@@ -8,13 +8,13 @@
     "preview": "vite preview"
   },
   "dependencies": {
-    "axios": "1.7.7",
+    "axios": "1.20.0",
     "pinia": "2.2.4",
     "vue": "3.5.12",
     "vue-router": "4.4.5"
   },
   "devDependencies": {
     "@vitejs/plugin-vue": "5.1.4",
-    "vite": "5.4.10"
+    "vite": "5.4.21"
   }
 }