Build: Adds a fallback script to fix package.json main and types fields before packaging (#59628)

scripts/prepare-packagejson.js

@@ -0,0 +1,21 @@
+const fs = require('fs');
+
+const cwd = process.cwd();
+const packageJson = require(`${cwd}/package.json`);
+
+const newPackageJson = {
+  ...packageJson,
+  main: packageJson.publishConfig?.main ?? packageJson.main,
+};
+
+if (packageJson.publishConfig?.types) {
+  newPackageJson.types = packageJson.publishConfig.types;
+}
+
+if (packageJson.publishConfig?.module) {
+  newPackageJson.module = packageJson.publishConfig.module;
+}
+
+try {
+  fs.writeFileSync(`${cwd}/package.json`, JSON.stringify(newPackageJson, null, 2));
+} catch (e) {}