Lenskit

A few small feature updates for LensKit 2025.

What's Changed
* Support auto-detecting key columns in ItemListCollection.from_df by mdekstrand in https://github.com/lenskit/lkpy/pull/659
* Support dataframe-format test data for batch recommendation by mdekstrand in https://github.com/lenskit/lkpy/pull/660
* Add PipelineCache to allow pipeline builders to cache component instances by mdekstrand in https://github.com/lenskit/lkpy/pull/661
* Only warn once for users with missing test items in analysis by mdekstrand in https://github.com/lenskit/lkpy/pull/664


**Full Changelog**: https://github.com/lenskit/lkpy/compare/v2025.1.1...v2025.2.0

This is the first release in the new LensKit series, 2025.1.1!

LensKit 2025.1.1 brings a new design to LensKit, with a new generation of APIs that will enable better future flexibility and capability, and make it a lot easier to see the various software capabilities. It will also be easier to add new capabilities, such as content-based and knowledge-based recommenders.

We have plans for a lot of great new things on top of this new foundation, but code written for LensKit 0.14 and earlier will need to be udpated. See the [migration guide](https://lkpy.lenskit.org/stable/migrating.html) for details.

Improved logging and metrics — almost there!

What's Changed
* Add meaningful error on duplicate metrics by mdekstrand in https://github.com/lenskit/lkpy/pull/653
* Fix logic for monitors in nested workers by mdekstrand in https://github.com/lenskit/lkpy/pull/654


**Full Changelog**: https://github.com/lenskit/lkpy/compare/v2025.1.1rc4...v2025.1.1rc5

Not super happy with this being in an RC series, but this removes some old `util` code, keeping a deprecated shim for a bit, and adds the `lenskit doctor` command, along with multiple negatives in negative sampling.

This fixes a bug in ItemList.from_arrow when a column has null values.

Quick update to refactor CLI into a plugin-based design so one of the client projects can add new CLI commands.