Follow-up to #16276

The "ends_with?" method is just a Rails alias of Ruby's "end_with?" method.
Using the latter makes the code less brittle.

* Fix media attachment enumeration

* Switch media_attachments id to snowflake ids

Co-authored-by: Thibaut Girka <thib@sitedethib.com>

- 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

Fix #11969

* 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

Fix #11016

An explicit error allows user agents to know the error and Sidekiq to
retry.

* Fix incomplete account records being read

- Put account processing into redis lock
- Do not save until record is complete

* Fix spaces

* When accessing uncached media attachment, redownload it

* Prevent re-download of rejected media