Improve task order upload validation handling.

- Display validation errors.
- Rerender validated form data correctly.
- Clear error state correctly.

translations.yaml

@@ -336,6 +336,7 @@ forms:
     list_items_unique_message: Items must be unique
     name_message: 'This field accepts letters, numbers, commas, apostrophes, hyphens, and periods.'
     phone_number_message: Please enter a valid 5 or 10 digit phone number.
+    file_length: Your file may not exceed 50 MB.
 fragments:
   edit_application_form:
     explain: AT-AT allows you to create multiple applications within a portfolio. Each application can then be broken down into its own customizable environments.