Build cli using rollup.

rollup.tracker.config.js

@@ -0,0 +1,13 @@
+import 'dotenv/config';
+import buble from '@rollup/plugin-buble';
+import resolve from '@rollup/plugin-node-resolve';
+import { terser } from 'rollup-plugin-terser';
+
+export default {
+  input: 'tracker/index.js',
+  output: {
+    file: 'public/umami.js',
+    format: 'iife',
+  },
+  plugins: [resolve(), buble(), terser({ compress: { evaluate: false } })],
+};