Board translation added

You can now translate posts and comments on the board into your language.

1. How to use

• A "Translate" button appears above each post and at the right end of each comment's nickname line. Tap it to translate, and tap it again to see the original.
• The translation language follows your app or browser language. You can change it with the arrow next to the button, and your choice is remembered on that device.
• The button does not appear on posts already written in your language.
• Translation is available to logged-in members.
• Only the text is translated. Photos and videos stay as they are.
• Translations are automatic, so some wording may feel unnatural. Use "Show original" to check the exact meaning.

2. Write in the language you are comfortable with

• Notices will still be posted in English and Japanese as before.
• Feel free to write posts and comments in your own language. Other members can read them through translation.