Resolve inconsistent parameter names via aliasing + deprecationwarning. (#3332)

* consistently rename Shuffles -> shuffles

* consistently rename Snapindex -> snapshotindex

* consistently rename batchsize -> batch_size

* consistently rename displayiters saveiters maxiters -> display_iters save_iters, max_iters

* consistently rename comparisonbodyparts -> comparison_bodyparts

* update `renamed_parameter`: add guards for chaining or typos + rules in docstring

* add tests for renamed_parameter: chaining and not in signature

* fix shuffle type hint in compat.py

* fix type hint for batch_size in compat.py

Co-authored-by: Copilot Autofix powered by AI <175728472+Copilot@users.noreply.github.com>

* address copilot review: fix typos and test_deprecation

* test_deprecation: add test multiple subsequent renames allowed

* consistently rename videotype, video_type -> video_extensions

* Additional renames video_type -> video_extensions

* update functional tests: videotype -> video_extensions

* Update deeplabcut/utils/deprecation.py

Co-authored-by: Cyril Achard <cyril.achard@epfl.ch>

* flag function signatures in pose_estimation_3d for later refactor

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Co-authored-by: Copilot Autofix powered by AI <175728472+Copilot@users.noreply.github.com>
Co-authored-by: Cyril Achard <cyril.achard@epfl.ch>