Add support for exporting bboxes in VIA-tracks

[sfmig]

Is your feature request related to a problem? Please describe.
Right now we support reading VIA-tracks files but not exporting in that format. This is sometimes a bit limiting for us, even if the format is not very widely used.

Describe the solution you'd like
To add an export function that exports a movement bboxes dataset in VIA-tracks format.

Describe alternatives you've considered
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Additional context
Currently in the docs we provide a snippet demoing how to export bboxes as csv files.

[SanjayUG]

Hi @sfmig ,

Could you please review my PR and approve the workflows? The PR adds the VIA-tracks export functionality for bounding boxes.

Thank you!

[niksirbi]

There seem to be two PRs #497 and #498 addressing the same issue. In general, please check if a draft PR already exists for the issue before opening a new one.

Sofía is currently away but I'm sure she'll take a look at these PRs when she's back.

Meanwhile, I've approved CI workflows so you @SanjayUG and @harsh-bhanushali-05 can proceed with debugging your PRs. It may help to also look at each other's implementations and see where/how they differ.

[sfmig]

Once this is implemented, we should extend the following tests (introduced in PR #503) to run on bbox data too:

• test_dimension_slider_with_nans
• test_dimension_slider_multiple_files

[SanjayUG]

Thank you @sfmig,

We would be working on it.