feat(lint): add ESLint configuration for admin and storefront applications

- Introduced eslint.config.mjs files for both admin and storefront to extend Next.js linting rules.
- Updated package.json files to replace the default Next.js lint command with a direct ESLint command for improved linting control.

apps/storefront/package.json

@@ -6,7 +6,7 @@
     "dev": "next dev --port 3000",
     "build": "next build",
     "start": "next start",
-    "lint": "next lint",
+    "lint": "eslint .",
     "type-check": "tsc --noEmit"
   },
   "dependencies": {