Prevent unsafe js reflection like Object.entries(), to better support property renaming

Using Object.entries() can cause code to break when using a compiler that has property renaming enabled, which is common for 1P.

Context for Googlers:
[go/typescript-optimization-safety-testing](https://goto.google.com/typescript-optimization-safety-testing)

Look for existing lint rules or compiler checks in the codebase that flag unsafe reflection. The issue mentions property renaming optimizations common at Google; start by searching for 'Object.entries' usage in the source. Determine how to detect and prevent such patterns, possibly by adding a custom ESLint rule or a build-time check. Verify the fix works with the project's existing test suite for compilation safety.

索引モデルが issue の本文から書いたものです。