Decodes lowercase hex into bytes, for stores that keep hashes as text. Throws a
MALFORMED_OPERATION coded fault on an odd length or any character outside 0-9a-f — uppercase
digits are rejected — so a malformed head cannot decode into the wrong bytes.
fromHex(hex:string):Uint8Array
Decodes a lowercase hex string back into its byte array.
Throws on an odd length or any non-hex-digit character. Such input is a caller bug to fix at
the source, not a recoverable outcome.
Decodes lowercase hex into bytes, for stores that keep hashes as text. Throws a MALFORMED_OPERATION coded fault on an odd length or any character outside
0-9a-f— uppercase digits are rejected — so a malformed head cannot decode into the wrong bytes.