tests/mutation.rs runs a seeded mutation pass over the test images and
small SOF9, SOF10 and 12-bit seeds, checking that decode never panics
and stays within small limits. fuzz/ is a cargo-fuzz crate (own
workspace) with a decode target and those seeds. jpeg.yml runs fmt,
clippy, tests and a wasm32 check on Linux. The README gains a testing
section.