feat: gaze_dataframe.unnest() supports multi-col unnest

[theDebbister]

Description

Gaze dataframe now supports unnest for multiple columns at the same time. If no args are given, it will unnest all possible values.
Fixes issue #446

Implemented changes

• Add support for passing a list of column names as the input_column in GazeDataFrame.unnest()
• can only specify output cols if only one input col needs to be unnested
• Automatically infer list of columns to be unnested if None

Type of change

• New feature (non-breaking change which adds functionality)

How Has This Been Tested?

Please describe the tests that you ran to verify your changes.
Provide instructions so we can reproduce.
Please also list any relevant details for your test configuration

• Test A
• Test B

Checklist:

• My code follows the style guidelines of this project
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• My changes generate no new warnings
• I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes
• Any dependent changes have been merged and published in downstream modules
• I have checked my code and corrected any misspellings

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Comparison is base (f9c43dd) 100.00% compared to head (fd9f0fb) 100.00%.

Additional details and impacted files

@@            Coverage Diff            @@
##              main      #592   +/-   ##
=========================================
  Coverage   100.00%   100.00%           
=========================================
  Files           52        52           
  Lines         2349      2352    +3     
  Branches       588       590    +2     
=========================================
+ Hits          2349      2352    +3     

Files	Coverage Δ
src/pymovements/dataset/dataset_files.py	100.00% <100.00%> (ø)
src/pymovements/gaze/gaze_dataframe.py	100.00% <100.00%> (ø)

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[dkrako]

Thank you for this great work!

There are three details which need some improvement.
Regarding the name of the input column argument, let's vote for the name on friday.

I myself am in favor of input_column.

[dkrako]

Thanks a lot for your endurance while finishing this PR!