RFC v0.2 R1 — Idempotency-Key replay window for POST
/api/v1/events/{event}/timetable/move. Narrow scope by design: the
12-hour ARCH §10 default would let a cached cascade-bump response
overwrite a fresh edit; 60 seconds covers honest network retry but
expires before a meaningful conflict can emerge.
Backed by the Laravel Cache facade (Redis in non-test env). Cache key
namespace `idempotency:60s:*` distinct from FormSubmission's
DB-column idempotency. Replays carry an `Idempotency-Replayed: true`
header so observability can distinguish them.
Registered as the route-middleware alias `idempotency.60s` in
bootstrap/app.php; will be applied on the move route in Step 8.
Missing or empty Idempotency-Key returns 400 with
`{"error":"idempotency_key_required"}`.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
bert.hausmans
546f121ee8