Add BCP 47 redirects for non-standard MediaWiki language codes

[HakanIST]

MediaWiki core maps several non-standard wiki language codes to standard BCP 47 codes in HTML lang= attributes (via LanguageCode.php). The Universal Language Selector reads these lang attributes but cannot find the BCP 47 codes in the language database, causing those languages to be silently dropped from the Vector 2022 language sidebar.

This adds redirects for the 4 missing BCP 47 codes:

• jv-x-bms → map-bms (Basa Banyumasan)
• nap-x-tara → roa-tara (Tarandíne)
• nrf → nrm (Nouormand)
• ro-cyrl-md → mo (Moldovan)

Bug: https://phabricator.wikimedia.org/T391575

[Nikerabbit]

We don't want non-standard codes in language-data.

[HakanIST]

Thanks for the quick feedback, @Nikerabbit!

Just to clarify: the codes being added here (nrf, jv-x-bms, nap-x-tara, ro-Cyrl-MD) are actually the standard BCP 47 equivalents, while the existing entries (nrm, map-bms, roa-tara, mo) are the non-standard ones. But I understand if this isn't the right place for the fix.

I also noticed that the ULS rewrite (resources/ext.uls.rewrite/) imports language-data.json directly, bypassing ext.uls.common.js where the als → gsw style redirects live. So a fix only in ext.uls.common.js wouldn't carry over to the new selector.

What would be the preferred approach here?

[HakanIST]

Thanks for the feedback @Nikerabbit. After further investigation, adding redirects in ext.uls.common.js (following the existing als/gsw pattern) should be sufficient to fix the issue. I'll pursue the fix in the ULS extension via Gerrit instead. Closing this PR.