Update pydantic to 2.12.1

[cdce8p]

Proposed change

https://github.com/pydantic/pydantic/releases/tag/v2.12.1
pydantic/pydantic@v2.12.0...v2.12.1

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• Dependency upgrade
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[bdraco]

Important note for Python 3.14 update: The core functionality of Pydantic V1 is not compatible with Python 3.14 or greater.

So any integrations still using Pydantic v1 compat will break on 3.14

[cdce8p]

Important note for Python 3.14 update: The core functionality of Pydantic V1 is not compatible with Python 3.14 or greater.

So any integrations still using Pydantic v1 compat will break on 3.14

Not entirely correct. From my testing so far, especially for #153939, most remaining uses of Pydantic v1 do work fine actually. AFAICT it's mostly those which only use really basic stuff or those which use from __future__ import annotations. The only truly incompatible dependency I've found is pyatv. Just waiting for a review on my PR there postlund/pyatv#2736.

Though there is always the possibility that real world testing will reveal one or two more incompatible dependencies of course.