Use concise message to show diagnostics in playground (#17357)
## Summary
This PR fixes the playground to use the new `concise_diagnostic` method.
## Test plan
**Before:**
<img width="1728" alt="Screenshot 2025-04-11 at 11 37 34 AM"
src="https://github.com/user-attachments/assets/cbfcbc52-2e70-4277-9363-ba197711390e"
/>
**After:**
<img width="1728" alt="Screenshot 2025-04-11 at 11 38 03 AM"
src="https://github.com/user-attachments/assets/356ec63c-50d9-49a8-8df4-84000b46fb6d"
/>
