chore: add Japanese README file and update main README to link it

[kiwamizamurai]

📝 Summary

🔍 Description of Changes

📋 Checklist

• I have read the contributor guidelines.
• For large changes, or changes that affect the public API: this change was discussed or approved through an issue, on Discord, or the community discussions (Please provide a link if applicable).
• I have added tests for the changes made.
• I have run the code and verified that it works as expected.

📜 Reviewers

@akshayka OR @mscolnick

[vercel]

The latest updates on your projects. Learn more about Vercel for Git ↗︎

Name	Status	Preview	Comments	Updated (UTC)
marimo-storybook	✅ Ready (Inspect)	Visit Preview	💬 Add feedback	Jan 20, 2025 11:37am

[vercel]

@kiwamizamurai is attempting to deploy a commit to the marimo Team on Vercel.

A member of the Team first needs to authorize it.

[github-actions]

Thank you for your submission, we really appreciate it. Like many open-source projects, we ask that you sign our Contributor License Agreement before we can accept your contribution. You can sign the CLA by just posting a Pull Request Comment same as the below format.

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I have read the CLA Document and I hereby sign the CLA

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[mscolnick]

thanks @kiwamizamurai! do you mind signing the CLA (if you read the messages above)

[kiwamizamurai]

I think that it's ok

I have read the CLA Document and I hereby sign the CLA

[github-actions]

🚀 Development release published. You may be able to view the changes at https://marimo.app?v=0.10.16-dev1