🔧 chore(validate.py): add multiline option to input_variables field in add_new_variables_to_template function

The multiline option is added to the input_variables field in the add_new_variables_to_template function. This allows the field to accept multiline input, which can be useful in certain scenarios where multiple lines of text need to be entered.

src/backend/langflow/api/v1/validate.py

@@ -71,6 +71,7 @@ def add_new_variables_to_template(input_variables, prompt_request):
                 field_type="str",
                 show=True,
                 advanced=False,
+                multiline=True,
                 input_types=["Document", "BaseOutputParser"],
             )