Small updates to pages with multiple annotation sets

[absempere]

From Tanya:

1. Instead of listing out each file, can we have a drop-down selector like we do for the same page on the back end? We don't need to add "AV File," just the selector https://avannotate.netlify.app/en/projects/tanyaclement+harvard-1953/events/30f86c81-cb93-436a-9b14-8599257f4308
2. I don't think we need to number the tapes (1-4 in this example), just list them in order.
3. There are still extra lines after This file is hosted offline.

See the published page here: https://tanyaclement.github.io/harvard-1953/events/august-4-1953-afternoon/

vs. the admin interface:

Main goal is to make the top matter on the published page more compact. That way we get to the annotations more quickly, and there's more screen space for annotations.

[absempere]

Based on today's conversation, the published page should look more like the admin-client:

Please remove the event label. Instead it should show:

AV File [drop down without numbers].

Replace This file is hosted offline. with the text No media is available.