cslib#307 adaptations for nightly-2026-01-30

Stream: nightly-testing

[github mathlib4 bot]

chore: adaptations for nightly-2026-01-30 cslib#307

Please review this PR. At the end of the month this diff will land in 'main'.

[Chris Henson]

Sorry about the noise on these PRs today. The merge strategy created some confusion in the situation where a theorem broke in nightly-testing had since been differently fixed in main. I fixed it manually and have merged.