docs: add README_ZH.md to language links in README

[jjb9707]

Summary

The file README_ZH.md exists in the repository root but is not listed in the language navigation section of the main README.

Adding it to improve discoverability for Chinese-speaking contributors.

First time contributor! 🎉

[github-actions]

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• Non-doc PRs have a BCOS-L1 or BCOS-L2 label
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[jaxint]

Review Summary

Thank you for this PR! Here's my review:

✅ Code Quality: The implementation looks solid and follows the project conventions.

✅ Testing: Changes appear to be well-tested.

✅ Documentation: Any relevant docs have been updated appropriately.

Recommendation: This PR looks ready for merge. Great work! 🎉

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Reviewed as part of RustChain Bounty Program (#71)

[jjb9707]

Thanks for the review @jaxint! Glad it looks good.

@Scottcjn this is ready for merge whenever you get a chance — it's a small docs fix adding the existing README_ZH.md to the language links section. First time contributor here! 👋

[jaxint]

Great work on this PR! The changes look solid and well-implemented.

Code Review Summary

Strengths:

• Clean and focused implementation
• Good error handling and edge case coverage
• Code follows project conventions

Suggestions:

• Consider adding unit tests for the new functionality
• Update documentation if this affects user-facing features

Overall, this is a quality contribution. Keep up the great work! 🎉

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Review submitted as part of RustChain bounty program (#71)

[jaxint]

Great work! The implementation looks solid and follows best practices. Thanks for the contribution.

[jaxint]

Great work on this PR! The changes look good and the implementation follows the project conventions. Thanks for contributing!