Co-authored-by: petrokoriakin1 <116151189+petrokoriakin1@users.noreply.github.com>

Co-authored-by: petrokoriakin1 <116151189+petrokoriakin1@users.noreply.github.com>
Co-authored-by: Effy Elden <effy@effy.space>

* Add tests

* Fix error when rendering public pages with media attachments

* Add tests

* Fix tests

* Please CodeClimate

(broken because I forgot to adapt it to glitch-soc's theming system)

Fixes #14092

Fix #11969

* Add audio uploads

Fix #4827

Accept uploads of OGG, WAV, FLAC, OPUS and MP3 files, and converts
them to OGG. Media attachments get a new `audio` type. In the UI,
audio uploads are displayed identically to video uploads.

* Improve code style

Fix #11016

* Save metadata from video attachments, put correct dimensions into OG tags

* Add twitter:player for videos

* Fix code style and test

* Add spec for media controller

* Add MediaAttachment.attached scope

* Simplify methods in media controller

for local attachments, use them in URLs. Check status privacy
before redirecting to actual file.