The FIX 4 test asserted a full new 201 emission after the only document
under an idempotency key was soft-deleted. That over-reached: the surviving
FiscalIdempotencyKey (never soft-deleted, by design) still collides on the
UNIQUE(product_id, idempotency_key), and the camada-2 winner lookup — now
filtered by deleted_at IS NULL — returns None and re-raises. Re-emission
under a burned key is a future CANCEL feature (no soft-delete path exists in
F2), out of scope for this MINOR. The fix's real contract is narrow: a replay
must not RETURN a soft-deleted document. Test now proves exactly that on the
query (seeded on a separate session so it doesn't pollute the app's shared
db_session — the source of the MissingGreenlet the end-to-end POST hit).
Detection proven: filter removed -> FAILED; restored -> passed.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
