message: catalog-backend: add alpha setup to package.json
diff: "publishConfig": {
  "access": "public",
  "main": "dist/index.cjs.js",
  - "types": "dist/index.d.ts"
  + "types": "dist/index.d.ts",
  + "alphaTypes": "dist/index.alpha.d.ts"
  },
  "backstage": {
  "role": "backend-plugin"
  ],
  "scripts": {
  "start": "backstage-cli package start",
  - "build": "backstage-cli package build",
  + "build": "backstage-cli package build --experimental-type-build",
  "lint": "backstage-cli package lint",
  "test": "backstage-cli package test",
  "prepack": "backstage-cli package prepack",
  },
  "files": [
  "dist",
  + "alpha",
  "migrations/**/*.{js,d.ts}",
  "config.d.ts"
  ],
  