revert: "refactor!: drop e-invoicing integration from erpnext (#26940)"

This reverts commit c335962827.

erpnext/patches/v14_0/restore_einvoice_fields.py

@@ -0,0 +1,24 @@
+import frappe
+from frappe.custom.doctype.custom_field.custom_field import create_custom_fields
+
+from erpnext.regional.india.setup import add_permissions, add_print_formats
+
+
+def execute():
+	# restores back the 2 custom fields that was deleted while removing e-invoicing from v14
+	company = frappe.get_all('Company', filters = {'country': 'India'})
+	if not company:
+		return
+
+	custom_fields = {
+		'Sales Invoice': [
+			dict(fieldname='irn_cancelled', label='IRN Cancelled', fieldtype='Check', no_copy=1, print_hide=1,
+				depends_on='eval:(doc.irn_cancelled === 1)', read_only=1, allow_on_submit=1, insert_after='customer'),
+
+			dict(fieldname='eway_bill_cancelled', label='E-Way Bill Cancelled', fieldtype='Check', no_copy=1, print_hide=1,
+				depends_on='eval:(doc.eway_bill_cancelled === 1)', read_only=1, allow_on_submit=1, insert_after='customer'),
+		]
+	}
+	create_custom_fields(custom_fields, update=True)
+	add_permissions()
+	add_print_formats()