collab_panel: Add small design adjustments (#52994)

Some tiny tweaks so that things look just a bit tidier in the collab
panel.

| Before | After |
|--------|--------|
| <img width="594" height="276" alt="Screenshot 2026-04-02 at 11  39@2x"
src="https://github.com/user-attachments/assets/f542d131-dbc5-41eb-bc13-0ebce3cf19a6"
/> | <img width="592" height="260" alt="Screenshot 2026-04-02 at 11 
34@2x"
src="https://github.com/user-attachments/assets/1198bc49-f780-433e-bb5d-6304f13703d6"
/> |

Release Notes:

- N/A
34c77a0eb9Danilo Leal committed on 4/2/2026, 6:27:35 PM· committed by GitHubparentcb99ab4
1 file changedLine totals unavailable