perf(build): finalize build optimization and address PR feedback

scripts/build_package.js

@@ -1,46 +0,0 @@
-/**
- * @license
- * Copyright 2025 Google LLC
- * SPDX-License-Identifier: Apache-2.0
- */
-
-//
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-//     http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-import { execSync } from 'node:child_process';
-import { writeFileSync, existsSync, readFileSync } from 'node:fs';
-import { join } from 'node:path';
-
-if (!process.cwd().includes('packages')) {
-  console.error('must be invoked from a package directory');
-  process.exit(1);
-}
-
-// build typescript files incrementally
-execSync('tsc -b', { stdio: 'inherit' });
-
-// Check for copy:assets script in package.json
-const packageJson = JSON.parse(readFileSync('package.json', 'utf8'));
-if (packageJson.scripts && packageJson.scripts['copy:assets']) {
-  execSync('npm run copy:assets', { stdio: 'inherit' });
-} else {
-  // fallback to generic copy
-  execSync('node ../../scripts/copy_files.js', { stdio: 'inherit' });
-}
-
-// touch dist/.last_build
-const distDir = join(process.cwd(), 'dist');
-if (existsSync(distDir)) {
-  writeFileSync(join(distDir, '.last_build'), '');
-}
-process.exit(0);