Schema reality (varchar(64), accommodating SHA-256 hex digest) diverges
from RFC v0.2 §5.3 ("ULID unique nullable"). Session 1 implementation is
correct; RFC needs amendment in next legitimate cycle. Tracked under
RFC-TIMETABLE-V0.2-PORTAL-TOKEN-SCHEMA-AMEND. Distinct from
RFC-TIMETABLE-V0.2-DOC-CLEANUP (which covers stale cross-references).
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>