frontend - session management - provide additional course context on the "Back to sessions" link

add the external course id (fallback to course title if no external course id exists) and its publication status indicator icon next to the "back to session" links.

<img width="1743" height="312" alt="Image" src="https://github.com/user-attachments/assets/5bda26f1-25a5-416d-831c-940d3db8eb50" />