* docs: expand bubble sort docstrings with algorithm explanation
Add a concise description of how bubble sort works (repeated
adjacent comparisons/swaps until a pass makes no swaps) and note
time/space complexity for both the iterative and recursive
implementations. No behavior changes; all existing doctests pass.
* Fix Ruff 0.16 lint failures
* S310
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Co-authored-by: Christian Clauss <cclauss@me.com>