feat: get_valuation_rate batch wise

This function is used to show valuation rate on frontend and also as
fallback in case values aren't available. Add "batch_no" param to get
batch specific valuation rates.

Co-Authored-By: Alan Tom <2.alan.tom@gmail.com>

erpnext/controllers/selling_controller.py

@@ -394,6 +394,7 @@ class SellingController(StockController):
 						"posting_time": self.get('posting_time') or nowtime(),
 						"qty": qty if cint(self.get("is_return")) else (-1 * qty),
 						"serial_no": d.get('serial_no'),
+						"batch_no": d.get("batch_no"),
 						"company": self.company,
 						"voucher_type": self.doctype,
 						"voucher_no": self.name,