Annotation exporting

[danton267]

• Adds Dash UI and callbacks to download annotations
• Adds figure annotation conversion to a suitable format with all relevant metadata

TODO:

• finish creating format compatible with napari

[github-actions]

Staging application has been deployed and is available at: https://dash5-services.plotly.host/ml-exchange-staging
Production app name: ml-exchange
Current branch name: annotation-exporting
Commit: 72e2542

[hannahker]

@danton267 see #56 for some suggested fixes.

[hannahker]

@danton267 -- super minor change requested by LBL: Can we update the output .npy files so that there's 1 file per annotated slice? So for example, if the user annotates slices 1 and 34, the outputs should be:

• mask_001.npy
• mask_034.npy

[danton267]

@danton267 -- super minor change requested by LBL: Can we update the output .npy files so that there's 1 file per annotated slice? So for example, if the user annotates slices 1 and 34, the outputs should be:

done! The mask data is now exported as .zip with one .npy (or .sp) file per slice