Accept liberally, emit conservatively (764a4d4): the gate is 8-4-4-4-12
hex in any case and any UUID version — uuidgen and UUID().uuidString
print uppercase, and a strict lowercase gate would silently stray an
agent's standard-tool card. Identity comparison is UUID-value equality
everywhere: ItemID keeps its byte-faithful rawValue but equates and
hashes on the lowercased canonical form, and the writer's
import-boundary collision check canonicalizes, so a same-UUID arrival
spelled in another case remints instead of slipping past. The app still
mints only lowercase v4 and never renames to canonicalize.
Full suite 342 tests in 63 suites green. Two findings filed.
Claude-Session: https://claude.ai/code/session_018BjQRYBR6jQja3jCRi5S3A
18 golden fixture boards as real on-disk trees under Fixtures/ — ten
valid/tolerated cases (rich board, interrupted create, non-UUID strays,
stray files, tombstones, tie-breaks, unknown-key order, coercion,
last-wins duplicates, board-level deleted) and eight fail-fast cases,
each pinned to its exact error reason and path; the rich board's whole
tree round-trips byte-identically. Pins two contract subtleties now
recorded in the design: tombstone flags are not inherited (renderers
walk ancestors) and last-wins resolves before order strictness. README
gains the storage-foundation feature entry. 146 tests total.
Claude-Session: https://claude.ai/code/session_018BjQRYBR6jQja3jCRi5S3A