More robust loops.video parsing

[EricBAndrews]

Note

This issue is on hold pending loops.video going open source and their API maturing

Update loops.video parsing to be more robust:

• Determine whether the host is a loops host without hardcoding (e.g., though a /site equivalent)
• Extract media URL without parsing raw HTML

[Sjmarf]

I did look into their api btw, but half of the app uses api/v0 and half uses api/v0.5 so it's probably not a wise idea to use it in its current form 🥴