fix(pos): multiple pos fixes and additions (#24227)

* fix: make custom fields in pos invoice similar to sales invoice

* feat: allow/disallow rate & discount change

* fix: any pos profile can be selected while creating pos opening

* fix: cannot add item to cart

* fix: validate phone payment only if payment request exists

* fix: replace pos payment method patch

* chore: rearrange item & customer group filter

* fix: allow/disallow invoice level discount

* fix: updating qty of item with uom having space char

* fix: move configuration checbox to config section

* fix: invalid item rate trigger

* fix: cannot remove item from draft invoices

* fix: customer currency not set in pos invoice

* fix: duplicate item error message

* fix: sales uom not fetched in pos invoice

* fix: cannot add taxes to pos invoice for uae region

* fix: cannot merge pos invoice into credit note

* fix: tax calculation while merging pos invoices

* feat: delete draft orders from order list

* fix: merging of pos invoice with pricing rules

erpnext/controllers/taxes_and_totals.py

@@ -107,7 +107,7 @@ class calculate_taxes_and_totals(object):
 					elif item.discount_amount and item.pricing_rules:
 						item.rate =  item.price_list_rate - item.discount_amount
 
-				if item.doctype in ['Quotation Item', 'Sales Order Item', 'Delivery Note Item', 'Sales Invoice Item']:
+				if item.doctype in ['Quotation Item', 'Sales Order Item', 'Delivery Note Item', 'Sales Invoice Item', 'POS Invoice Item']:
 					item.rate_with_margin, item.base_rate_with_margin = self.calculate_margin(item)
 					if flt(item.rate_with_margin) > 0:
 						item.rate = flt(item.rate_with_margin * (1.0 - (item.discount_percentage / 100.0)), item.precision("rate"))