Improve docs translation from English to Japanese

[lilin90]

The current quality of machine translation for Japanese docs is not so good. We need to consider other solutions. @shhdgit has tested OpenAI (as listed below), but still have some known issues (lost Markdown format, context alignment, overlarge size of a single .md file, etc.) to resolve.

• https://github.com/pingcap/docs/blob/master/.github/workflows/translation.yaml
• Previous testing https://github.com/shhdgit/docs-1/pull/8/files

In addition, more planned improvements are listed as follows:

• Switch from Google Translate to OpenAI for Japanese docs translation #19658
• Translate the metadata (title, summary) of each file to Japanese for SEO #19655
• Change the current English links to Japanese links for JA docs #19656
• Improve terms or glossary translation in Japanese docs #19657

[shhdgit]

We have already applied AI summaries to the description but not the title. We can also process the titles as the description.

https://github.com/pingcap/docs/pull/16947/files
https://github.com/shhdgit/doc-summarizer

[likidu]

We can do some early test using ChatGPT Plus 4o model to compare with our current translation solution.