[ENH] K-Means anomaly detector

[SebastianSchmidl]

Reference Issues/PRs

Depends on #1605

What does this implement/fix? Explain your changes.

Introduces a new anomaly detection algorithm: KMeansAD with tests and docs.

Does your contribution introduce a new dependency? If yes, which one?

no

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[aeon-actions-bot]

Thank you for contributing to aeon

I would have added the following labels to this PR based on the changes made: [ $\color{#6F6E8D}{\textsf{anomaly detection}}$ ], however some package labels are already present.

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[TonyBagnall]

very nice documentation

[MatthewMiddlehurst]

Left some comments on the related PR, should merge that first.