- Change audio files to not be stripped of metadata
- Automatically extract cover art from audio if it exists
- Add `thumbnail` parameter to `POST /api/v1/media`, `POST /api/v2/media` and `PUT /api/v1/media/:id`
- Add `icon` to represent it in attachments in ActivityPub
- Fix `preview_url` containing URL of missing missing image when there is no thumbnail instead of null
- Fix duration of audio not being displayed on public pages until the file is loaded
* Change domain blocks to automatically support subdomains
If a more authoritative domain is blocked (example.com), then the
same block will be applied to a subdomain (foo.example.com)
* Match subdomains of existing accounts when blocking/unblocking domains
* Improve code style
