When an AACS-encrypted ISO is muxed with decryption requested (not --raw)
but key resolution yielded no usable key, input() proceeded to mux the
still-encrypted stream — emitting ~100 MB of garbage (no TS syncs, demuxer
emits nothing) and sometimes spinning for tens of minutes.
Add a cheap result-check in resolve::input()'s Iso branch via the pure
predicate aacs_key_missing(raw, has_aacs, keys): when decryption is
requested AND the disc carries AACS state AND decrypt_keys() is None,
return new Error::NoDiscKey { disc_hash } (E7022) before muxing. The
40-hex disc hash is sourced from AacsState::disc_hash. --raw and
non-AACS (unencrypted / CSS) discs are unaffected. Unit-tested.
MattJackson
b7405e2d27