v1.32.0 -- Receiving performance, customer email on sales orders

Receiving performance on large purchase orders, and customer email carried through onto the sales order.

Changed

Handheld receive line list is paged (#435). The receive screen rendered every PO line as a row in a ScrollView and re-rendered all of them on each scan, so receiving a 700-line purchase order stuttered in proportion to its size. The list is now paged 50 at a time behind a memoized sort, the way Pick and PutAway already bound their lists, so the rendered row count no longer grows with the PO. The sort and paging logic moves into mobile/src/utils/receiveLines.js with its own tests.

Fixed

Per-item PO line lookup no longer scans the whole PO (#435). receive_items resolved each received item's line with WHERE po_id AND item_id, but purchase_order_lines was indexed on po_id alone, giving an O(lines) scan per item and O(lines²) across a full receive. Migration 077 adds a composite (po_id, item_id) index and drops the now-redundant single-column one, whose po_id prefix the composite still covers. Receiving-bin validation is memoized as well, so a client sending one bin for every scan does not re-query it per item.

Added

Customer email on sales orders (#436). POS checkout already collected customer_email as a receipt and loyalty capture field, but there was no column on sales_orders for it to land in, so the value was dropped on the way through. Migration 078 adds it: free-text, nullable, no FK or CHECK, matching the other customer_* fields and customers.email. POS checkout writes it through, admin sales-order read and edit carry it, and the sales-order modal shows it in the summary with an editable input. The inbound mapping can populate it when the upstream payload carries an email; db/mappings/example-template.yaml.template documents the field, and a deployment whose sending system omits email leaves it unmapped so the column stays NULL. Display only.

Migrations

077 purchase_order_lines_po_item_index: adds a composite (po_id, item_id) index, drops the superseded ix_purchase_order_lines_po.

078 sales_orders_customer_email: adds customer_email VARCHAR(255) to sales_orders, nullable.

Mobile

The receive screen changes, so the mobile build moves to version 1.32.0, versionCode 11. The APK is rebuilt at the end of the current migration round rather than per release, so this build ships alongside the other pending mobile work.

Verification

Merged-main suites: api 2873 passed / 9 skipped, admin 101 passed, mobile 55 passed.