Renaming the pkg to treeple

[SUKI-O]

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[adam2392]

I tried this locally and there are a number of issues:

1. All directories must contain a meson.build file. I'm unsure how you approached this renaming, but I would just literally rename the directory and then ctrl+f and ctrl+replace "scikit-tree/sktree" -> "treeple". Rn, treeple/meson.build does not exist anymore.
2. https://stackoverflow.com/questions/4526910/rename-a-git-submodule specifies how to rename a git submodule. You just have to "rename" the file directory expected

Afterwards, I would expect an update to the changelog informing users how to transition their code.

An open question is do we want to encourage usage of the pattern: import treeple as tp vs from treeple import RandomForestClassifier?

[adam2392]

Apologies! I messed up the main branch, and as a result this PR auto-closed. Do you mind resubmitting it to main?