add biome as linter, formatter

package.json

@@ -5,7 +5,9 @@
   "scripts": {
     "dev": "astro dev",
     "build": "astro build",
-    "preview": "astro preview"
+    "preview": "astro preview",
+    "check": "biome check --write",
+    "ci": "biome ci"
   },
   "dependencies": {
     "@astrojs/mdx": "^4.3.0",
@@ -21,5 +23,8 @@
     "starlight-openapi": "^0.19.1",
     "tailwindcss": "^4.1.11",
     "vanilla-cookieconsent": "^3.1.0"
+  },
+  "devDependencies": {
+    "@biomejs/biome": "^2.0.6"
   }
 }