[ENH] Auto naive forecaster

[TonyBagnall]

Simple forecaster that chooses either naive, mean or seasonal based on train error (or "in sample" as they call it).

Seems like a sensible benchmark to me, although Ive not seen it used. Main issues are

1. It uses the train sample mean to measure performance
2. It evaluates seasonality for a max of 1/4 series length

could easily cross validate, but seems OTT for this algorithm.

[aeon-actions-bot]

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I have added the following labels to this PR based on the title: [ enhancement ].
I would have added the following labels to this PR based on the changes made: [ forecasting ], however some package labels are already present.

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