Implement `get_feature_names_out` for all estimators

This issue tracks the implementation of get_feature_names_out for all remaining estimators (follow-up work for #18444).

@thomasjpfan do you maybe have a list we could add here to track them?

Edit: let’s do it by modules since the common test is organized this way:

• #22255 cluster
• #22119 cross_decomposition
• #21334 decomposition
• #22120 discriminant_analysis
• ensemble
  • Partly done in #21762
  • https://github.com/scikit-learn/scikit-learn/pull/22695
  • https://github.com/scikit-learn/scikit-learn/pull/22697
• #21078 impute
• #22249 isotonic
• kernel_approximation
  • Partly done in #22137
  • Rest in https://github.com/scikit-learn/scikit-learn/pull/22694
• #22254 manifold
• #22212 neighbors
• #22248 neural_network
• #21079 preprocessing
• #21569 special case for FunctionTransformer
• #21330 random_projection

Note: some notes on how to generate feature names in general:

https://github.com/scikit-learn/enhancement_proposals/blob/master/slep007/proposal.rst#output-feature-names

[jeremiedbb]

Every item is checked. Closing. Thanks everyone !

[adrinjalali]

I guess we’re just figuring out what the public API should look like, once the API is stable, we can make them public.