Add the option to sort a Dataframe by several columns

[clefourrier]

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Is your feature request related to a problem? Please describe.
Users have requested to be able to sort the OpenLLMLeaderboard by several columns.
Example: we have a model type column in the ExtendedView (tab 2), and people would want to be able to sort by model type, then by average score, or by average score, then number of likes, ...

Describe the solution you'd like
I'd like users to be able to sort by several Columns in a Dataframe, which would imply the ability to "freeze" a primary sort column, then sort by a secondary column.

[pngwn]

Just to clarify, this would mean that if the 'frozen' primary sort column had duplicate entries, sorting the secondary column would just reorder those duplicates among themselves while keeping everything else in the same order?

[clefourrier]

Yes, exactly