feat: prepare nobat724_front for deployment on Liara platform

- Added Node.js engine requirement in package.json to ensure compatibility.
- Created liara-deploy.md for deployment instructions and environment setup.
- Added example environment variables in .env.liara.example for clarity.
- Introduced .liaraignore to exclude unnecessary files from deployment.
- Created liara.json for Liara configuration, including health check settings.
- Removed redundant next.config.mjs file to prevent configuration conflicts.

package.json

@@ -2,6 +2,9 @@
   "name": "nobat724",
   "version": "0.1.0",
   "private": true,
+  "engines": {
+    "node": ">=20"
+  },
   "scripts": {
     "dev": "cross-env HOST=yazd-nobat.localhost PORT=3000 NODE_TLS_REJECT_UNAUTHORIZED=0 next dev",
     "build": "next build",