New register → link KHQR/Bank STAGING

Next-Phase n13 (Narong). Full flow verified on demo.staging 5/5 + staging smoke 5/5.

Extends the n6 default-Cash setup: after a register is added, a prompt offers to set up a KHQR / Bank payment for it — link an existing bank method, or create a new one (pre-filled per Narong: name = "KHQR"/"Bank", description = {flavor} - {Shop} - {Register}). KHQR is a bank-type method (confirmed with Narong — "simple is better"), so no new payment type / migration; create + link is one call via the Item #7 register-payment junction.

End-to-end on demo.staging

KHQR method created + linked to the new register — After adding register `n13 304043` and choosing "New KHQR", the method lands on Payment Methods: type **Bank**, ABA · account 000 111 222, and **REGISTERS = n13 304043** — linked to that register specifically (not "All registers" like the default Cash).

The prompt + pre-filled form

KHQR/Bank prompt — Shown right after a register is added — link an existing bank method, or New KHQR / New Bank, or Skip.

Create KHQR form pre-filled — "New KHQR" → Name `KHQR`, Description `KHQR - {Shop} - {Register}` (Narong's format), bank preset + optional account → Create & link.

Checks

Add register → KHQR/Bank prompt appears	pass
New KHQR pre-filled → Create & link succeeds	pass
KHQR method created (Bank type, account, linked to the register)	pass
Full staging E2E	5/5
Staging smoke	5/5

nix-cafe dev 5325295 → staging 2f04127 (Worker nix-cafe-staging bd975fe7). 3 files, no migration. Parked on staging for the scheduled prod promote.