Add cash drawer kick on register cash payments

[osswald]

Summary

• Add per-register cash drawer ESC/POS command presets (none, pin 2/5, short/long) in cloud event configuration, with validation that a receipt printer must be linked when a drawer command is set.
• On the Pi, automatically send a cash drawer kick to the register's linked network receipt printer on every register cash payment (independent of receipt printing), and sync each open to the cloud as a cash_drawer transaction.
• Show cash drawer opens in the event Transaktionen tab as kassenschublade, with filter support in the cloud admin UI.

Test plan

• Configure a cash register with a network receipt printer and a cash drawer command preset in cloud event config; verify validation blocks drawer without printer.
• Complete a register cash payment on Pi; confirm drawer kick print job is enqueued and drawer opens (or bytes sent to printer).
• Verify cash drawer open appears in cloud Transaktionen with kind kassenschublade.
• Confirm no drawer kick on non-cash payments, non-register orders, or when command is none.
• Confirm receipt reprint does not trigger a second drawer kick.

Made with Cursor

[cursor]

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