2026.2.1 bug-fix release

[mdekstrand]

Couple of bug fixes, including a CLI failure, and one small feature (Arrow tables for entity attributes).

What's Changed

• fix graded NDCG crashes for invalid gain values by @samiravaez in fix graded NDCG crashes for invalid gain values #1096
• Improve CLI log configuration and iterative training logs by @mdekstrand in Improve CLI log configuration and iterative training logs #1106
• Support Arrow tables as inputs for adding item attributes by @mdekstrand in Support Arrow tables as inputs for adding item attributes #1109
• Move data import to lenskit.data.sources by @mdekstrand in Move data import to lenskit.data.sources #1110

Full Changelog: v2026.2.0...v2026.2.1

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This discussion was created from the release 2026.2.1 bug-fix release.