Add a top-level TODO.md for follow-up work that should not remain as scattered
inline source comments.
Document the current Check Console Privileges limitation, where console rights
are mapped to supervisor equivalence for now, and track the need for a real
console privilege map. Also record follow-ups for queue spool path case
handling, direct NCP 17/4c test coverage, Q_UNIX_PRINT backend improvements,
and deferred optional protocol work.
Reference TODO.md from the main README.
