checks: Configure isort and enable isort in CI

[echoix]

This PRs configures isort in pyproject.toml

It also enables checking in pre-commit and in CI, with suggestions.

To not fail uselessly, these PRs (that fix import sorting) must be merged:

• style(temporal): Sort and group imports #3959
• style: Sort and group imports on modules #3962
• style(scripts): Sort and group imports #3963
• style(gui): Sort and group imports for simple changes only #3964
• style: Sort and group imports in remaining files #3965
• The follow-up PR after style: Sort and group imports in remaining files #3965 for the real fixes in gui/wxpython folder

That way, the fixes in the above PRs will stay fixed in future.

[echoix]

I found out that I can further tune the config files for isort, and the output isn't exactly the same. I want to figure this out before pushing for the PRs

[echoix]

I'm dropping all of these PRs concerning isort for now... I already removed these from my working branch as there were too many conflicts, and I'll end up adding an exclusion for the pylint violations instead.

I might reconsider later, I will still be keeping the changes in a branch somewhere