* wrap thumbnailing code to handle generation natively where possible
* more code comments!
* add even more code comments!
* add code comments about blurhash generation
* maintain image rotation if contained in exif data
* move rotation before resizing
* ensure pix_fmt actually selected by ffprobe, check for alpha layer with gifs
* use linear instead of nearest-neighbour for resizing
* work with image "orientation" instead of "rotation". use default 75% quality for both webp and jpeg generation
* add header to new file
* use thumb extension when getting thumb mime type
* update test models and tests with new media processing
* add suggested code comments
* add note about thumbnail filter count reducing memory usage
* update to use webp for thumbnails
* bump webp quality up to 40% from 12% (it's a bit different to jpeg quality setting)
* update to use yuva colorspace, and use thumbnail=n=10 to select frame
* fix missing comma in ffmpeg args
* add links to appropriate ffmpeg docs
* update tests
* add file size tests for thumbnails
---------
Co-authored-by: tobi <tobi.smethurst@protonmail.com>
kim