Span status should be "unknown error" but is showing "unknown"

When sending spans to Sentry with a `status` of `unknown_error`, these show in the UI as having a status of `unknown`, which is confusing to SDK users. This was _originally reported in [#2514](https://github.com/getsentry/sentry-dotnet/issues/2514#issuecomment-3071169617)_ in the .NET SDK but I don't think it can be addressed in the SDK itself. The SDK is sending the span as: ```json { "span_id": "79ca9f101de64c64", "parent_span_id": "549459431681a0c1", "trace_id": "f5f184955e25c44a989428eb9613ae7f", "op": "Some sketchy business", "description": "Some sketchy business", "status": "unknown_error", "start_timestamp": "2025-07-14T21:53:13.321662+00:00", "timestamp": "2025-07-14T21:53:13.351699+00:00", "data": { "otel.status_description": "test with activity.RecordException", "otel.status_code": "ERROR", "otel.kind": "Internal" } } ``` So the status is quite clearly `unknown_error` and the data contains `"otel.status_code": "ERROR"`. However the UI in Sentry shows a status of `unknown`, which is a bit more ambiguous. <img width="1377" height="471" alt="Image" src="https://github.com/user-attachments/assets/e459de6e-6fb9-4153-be07-0bcc85d22dd9" />