Add MIT license to the project

- Create LICENSE file with MIT license text
- Update package.json with license field
- Copyright holder: Alejandro Gómez

package.json

@@ -3,6 +3,7 @@
   "private": true,
   "version": "0.1.0",
   "type": "module",
+  "license": "MIT",
   "scripts": {
     "dev": "vite",
     "build": "tsc -b && vite build",