Display captured exceptions in Response Body UI for empty error responses

[georgidhristov]

Description

After PR #37, DebugProbe now captures:

• ExceptionMessage
• ExceptionStackTrace

for unhandled exceptions where the ASP.NET Core response body is empty.

The UI still renders the ResponseBody section as empty.

Current Behavior

For requests like:

GET /Demo/GetUser/500

the backend correctly stores exception details, but the UI shows:

• Status: 500
• Response Body: Empty

even though exception information exists in the stored DebugEntry.

Expected Behavior

When:

• ResponseBody is empty
• and exception data exists

the UI should display the captured exception information inside the Response Body section (similar to Swagger exception output).

Example:

System.Exception: Database failure
   at DemoController.GetUser(...)
   at ...

UI Logic

Something similar to:

if (string.IsNullOrWhiteSpace(entry.ResponseBody) &&
    !string.IsNullOrWhiteSpace(entry.ExceptionStackTrace))
{
    // Render exception details instead of empty response body
}

Notes

This is a UI-only issue.

Backend exception capture was already implemented in PR #37.