Songs: Changing song language does not affect lyrics language

[szc126]

Website (required)

VocaDB

Describe the bug (required)

Changing song language (Basic info > Language) does not affect lyrics language (Lyrics > Original > Language).

Examples:
https://vocadb.net/Song/ViewVersion/1919121 (three languages)
https://vocadb.net/Song/ViewVersion/1919091
https://vocadb.net/Song/ViewVersion/1919090
https://vocadb.net/Song/ViewVersion/1919089
https://vocadb.net/Song/ViewVersion/1919088

To Reproduce (optional)

Steps to reproduce the behavior:

1. Go to the edit page of a song entry that has lyrics.
2. Change the song language under Basic info.
3. Save.
4. See error (the lyrics language has not changed, and the song will still show up in a search by language, under the unchanged lyrics' language)

Expected behavior (optional)

Lyrics language follows song language. The opposite (song language follows lyrics language) already happens instantly in the editor.

Desktop (optional)

• OS: Linux
• Browser: Firefox 122.0.1

Checklist (required)

Fill out the checklist. Use strikethroughs or leave fields empty if you don't know or are unable to check/test.

• Searched VocaDB/vocadb for duplicate issues.
• Tested on the beta site.
• Tested on different browsers (e.g. Firefox, Chrome, Safari, Edge).
• Checked in private mode.
• Cleared browser cache and cookies.
• Checked the DevTools console.
• Checked the syslog (mods+ only).

[FinnRG]

This was intentional at the time (#1408 (comment)) to mimic the frontend fallback, but I guess we can implement a warning or sync them automatically.