ASCII85 now rejects values outside the 32-bit group range
Whitespace, optional Adobe delimiters, z and legal partial groups are supported; malformed/overflowing groups are rejected.
Decode ASCII85 with optional delimiters, whitespace, partial final groups, and the z zero-block abbreviation.
Inspect decoded bytes as UTF-8, hexadecimal and byte count, then re-encode them to verify a lossless ASCII85 round trip.
Whitespace, optional Adobe delimiters, z and legal partial groups are supported; malformed/overflowing groups are rejected.