[BUG] Upload task is lost when applying BuildConfig triggers script compilation/domain reload

Describe the bug
When a BuildConfig changes the current scripting define symbols, Build Uploader applies the configuration and Unity starts script compilation. The resulting domain reload destroys the active UploadTask before the build begins.
The task disappears from the Upload Tasks window and no failed report is created. Starting the same upload again works because the BuildConfig settings already match.

To Reproduce

1. Create a BuildConfig whose scripting defines differ from the current Player Settings.
2. Add it as a BuildConfig source in an Upload Profile.
3. Start the upload.
4. Unity applies the settings and recompiles scripts.
5. After the domain reload, the build does not continue and the task is missing.
6. Start the upload again; it now succeeds.

Expected behavior
The upload should continue after applying the BuildConfig, or at minimum persist a failed/interrupted task with an actionable explanation.

Environment:
• Unity 6000.3.24f1
• Build Uploader 3.3.0
• Windows 11