During attachment upload Pleroma returns a "description" field. Pleroma-fe has an MR to use that to pre-fill the image description field, <https://git.pleroma.social/pleroma/pleroma-fe/-/merge_requests/1399>
* This MR allows Pleroma to read the EXIF data during upload and return the description to the FE
* If a description is already present (e.g. because a previous module added it), it will use that
* Otherwise it will read from the EXIF data. First it will check -ImageDescription, if that's empty, it will check -iptc:Caption-Abstract
* If no description is found, it will simply return nil, just like before
* When people set up a new instance, they will be asked if they want to read metadata and this module will be activated if so
This was taken from an MR i did on Pleroma and isn't finished yet.
Added ffmpeg/imagemagick checks to launch checks (if media preview proxy is enabled). Added documentation on installing optional media / graphics packages (imagemagick, ffmpeg, exiftool).
