refactor: remove esm module (#1077)

vitest.config.ts

@@ -0,0 +1,13 @@
+import { defineConfig } from 'vitest/config';
+
+export default defineConfig({
+  test: {
+    include: ['packages/**/*.spec.ts'],
+    testTimeout: 5000,
+    coverage: {
+      provider: 'istanbul', // or 'c8'
+      reporter: ['lcov'],
+      reportsDirectory: '.coverage/store',
+    },
+  },
+});