chore: add prettier formatting

package.json

@@ -7,6 +7,8 @@
     "build": "next build",
     "start": "next start",
     "lint": "eslint .",
+    "format": "prettier --write .",
+    "format:check": "prettier --check .",
     "typecheck": "tsc --noEmit",
     "notifications:worker": "node scripts/notification-worker.mjs"
   },
@@ -35,6 +37,7 @@
     "eslint": "^9.17.0",
     "eslint-config-next": "^16.2.6",
     "postcss": "^8.4.49",
+    "prettier": "^3.8.4",
     "tailwindcss": "^3.4.17",
     "typescript": "^5.7.2"
   }