Add timestamp for completion in the event of the calendar entry

I love how you add a green checkmark into my calendar entry when i click to complete a task (that is synced to my calendar).

I would like to have an option to enable timestamping when it was done and add it to the calendar entry description along with a green checkmark.

e.g., ===​=== Marked on: Sep 1, 2026, 3:28 PM EDT ===​===