Separate JSON API backend (vm_api.py) + React+TanStack frontend scaffold

- vm_api.py: pure FastAPI JSON API on :8098 with CORS
- vm-api.service: systemd unit for API (replaces inline HTML vm_web.py for frontend)
- vm_web.py: kept intact as fallback; Apache now proxies /api/ -> :8098
- frontend/: Vite + React + TanStack Query scaffold
- Apache vhost updated: DocumentRoot -> frontend/dist, /api/ proxy, SPA fallback
- All original HTML pages still functional via :8099 during transition

frontend/node_modules/@babel/compat-data/corejs2-built-ins.js

@@ -0,0 +1,2 @@
+// Todo (Babel 8): remove this file as Babel 8 drop support of core-js 2
+module.exports = require("./data/corejs2-built-ins.json");