🔧 chore(validate.py): add display_name field to TemplateField in post_validate_prompt function

The display_name field is added to the TemplateField object in the post_validate_prompt function. This field allows for a more user-friendly display of the variable name in the UI.

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

@@ -39,6 +39,7 @@ def post_validate_prompt(prompt: ValidatePromptRequest):
             try:
                 template_field = TemplateField(
                     name=variable,
+                    display_name=variable,
                     field_type="str",
                     show=True,
                     advanced=False,