debugger: Improve debugger panel empty state (#32889)

Before:

![CleanShot 2025-06-17 at 13 48
58@2x](https://github.com/user-attachments/assets/16ecebfa-871e-4a2d-b6a3-2178de70aaef)

After:

![CleanShot 2025-06-17 at 13 49
24@2x](https://github.com/user-attachments/assets/2d8a0444-6088-45f1-a880-0bdd0aef968e)


Release Notes:

- N/A (Beta: Improved the debugger panel when there are no currently
active sessions)
8883885ecbNate Butler committed on 6/17/2025, 6:50:46 PM· committed by GitHubparentdbc4ccd
5 files changedLine totals unavailable