feat: allow to edit Stock Quantity in the Sales and Purchase Transactions (#36600)

feat: allow to edit Stock Quantity in the Sales and Purchase transactions
diff --git a/erpnext/public/js/controllers/transaction.js b/erpnext/public/js/controllers/transaction.js
index 975adc2..b0a9e40 100644
--- a/erpnext/public/js/controllers/transaction.js
+++ b/erpnext/public/js/controllers/transaction.js
@@ -224,6 +224,14 @@
 		}
 
 	}
+
+	toggle_enable_for_stock_uom(field) {
+		frappe.db.get_single_value('Stock Settings', field)
+		.then(value => {
+			this.frm.fields_dict["items"].grid.toggle_enable("stock_qty", value);
+		});
+	}
+
 	onload() {
 		var me = this;
 
@@ -1191,6 +1199,16 @@
 		]);
 	}
 
+	stock_qty(doc, cdt, cdn) {
+		let item = frappe.get_doc(cdt, cdn);
+		item.conversion_factor = 1.0;
+		if (item.stock_qty) {
+			item.conversion_factor = flt(item.stock_qty) / flt(item.qty);
+		}
+
+		refresh_field("conversion_factor", item.name, item.parentfield);
+	}
+
 	calculate_stock_uom_rate(doc, cdt, cdn) {
 		let item = frappe.get_doc(cdt, cdn);
 		item.stock_uom_rate = flt(item.rate)/flt(item.conversion_factor);