Add build script

Author: zerodevx

build.mjs

@@ -0,0 +1,15 @@
+#!/usr/bin/env zx
+
+await $`npm run lint && npx svelte-package -o package && npx vite build -c vite.dist.config.js`
+const pkg = await fs.readJson('package.json')
+pkg.scripts = undefined
+await fs.writeJson('package/package.json', pkg, { spaces: 2 })
+await fs.copy('README.md', 'package/README.md')
+await fs.copy('LICENSE', 'package/LICENSE')
+await fs.copy('package/dist/index.umd.js', 'package/dist/index.umd.cjs')
+await $`cd package && npx publint`
+
+echo`
+To publish to npm, run:
+$ cd package && npm publish --access public
+`