fix(shift-closing): count partial-invoice payments in reconciliation

[NotAbdelrahmanelsayed]

Problem

When a cashier collects a payment against an existing partially-paid / due Sales Invoice (e.g. 500 cash on an invoice with an outstanding balance), the amount is recorded correctly as a Payment Entry — but it does not show up in the Close Shift reconciliation. The cashier ends up with a cash drawer that looks short by exactly the amount collected on due invoices.

Root cause

A reference_no mismatch between how the payment is created and how shift closing queries it:

	reference_no written
Normal POS invoice payment	<opening shift name> (e.g. POSA-OS-24-0000001)
Partial / due invoice payment	POS-<invoice name> (fallback)

get_payments_entries() in pos_closing_shift.py filters WHERE reference_no = <opening shift name>, so partial-invoice payments are never matched.

Fix

Thread the active opening shift from the POS UI down to the Payment Entry, so it is tagged with the shift name and discovered during reconciliation.

Backend — pos_next/api/partial_payments.py

• create_payment_entry() and add_payment_to_partial_invoice() accept an optional pos_opening_shift.
• When no explicit reference_no is supplied, the shift name is used as reference_no. The POS-<invoice> fallback is preserved for non-shift contexts.

Frontend

• InvoiceManagement.vue and PartialPayments.vue pass the current shift (useShift().currentShift?.name) when submitting a payment.

Result

Cash (and any mode of payment) collected on due/partial invoices during a shift now appears in the Close Shift reconciliation totals.

Scope

3 files, +16/−1. Backward compatible — pos_opening_shift is optional.