* don't set emoji / media image paths on failed download, migrate FileType from string to integer
* fix incorrect uses of util.PtrOr, fix returned frontend media
* fix migration not setting arguments correctly in where clause
* fix not providing default with not null column
* whoops
* ensure a default gets set for media attachment file type
* remove the exclusive flag from writing files in disk storage
* rename PtrOr -> PtrOrZero, and rename PtrValueOr -> PtrOrValue to match
* slight wording changes
* use singular / plural word forms (no parentheses), is better for screen readers
* update testmodels with unknown media type to have unset file details, update attachment focus handling converting to frontend, update tests
* store first instance in ffmpeg wasm pool, fill remaining with closed instances
* add more supported file types to our media processor that ffmpeg supports, update supported mime type lists
* add code comments to the supported mime types slice
* don't check for zero value string, just parse
* remove some unneeded consts which make the code a bit harder to read
* fix test expected instance media mime types, use compact ffprobe json, simple media processing by type
* final tweaks to media processing code
* don't use safe divide where we don't need to
