The server dedupes on client_uuid, but the tablet minted a fresh uuid
on every confirm() call — including retries after a timeout/dropped
connection, exactly the case the idempotency key exists to guard
against. The dedup check never fired on a real retry, so a flaky-Wi-Fi
resend could book the same sale twice.
Client: generate one uuid per pending cart (a ref, lazily created),
reuse it across retries of the same submission, reset it only when
the cart is cleared (success or cancel) so the next cart gets its own
id.
Server: the existing-row dedup check and the insert straddled the
db.transaction() boundary, so a genuine UNIQUE-violation race would
have surfaced as a raw 500 instead of the idempotent response. Catch
that specific violation and fall back to re-reading the row.
- admin: maroon buttons use .danger class (white text); replace hardcoded
#333/#ff8a8a/drop-target colors with theme vars so light mode is legible
- time.ts: force hourCycle h23 (no 24:00 artifact), drop dead 24-guard
- Makefile/README: rsync with excludes instead of `cp -a .` so .git and the
dev DB don't ship to /opt; add rsync to deps
- store created_at as UTC ISO; display/group in Europe/Berlin
- stats grouped by business day (sales night past midnight, 5am cutoff)
- add "Statistik zurücksetzen"
- allow deleting drinks/tresen (refused if referenced by sales)
- CSV exports local wall-clock time
