Type Alias: Ta1NoteCode

Ta1NoteCode = typeof TA1_NOTE_CODES[keyof typeof TA1_NOTE_CODES]

String-literal union over TA1_NOTE_CODES - the standard-issued note codes 000–028. Real-world inbound TA1 may carry a value past 028 (some revisions extend the list); parseTA1 exposes the raw string in that case so the verbatim value survives even when the union cannot statically type it.