## What changed
- Record the effective detail setting and source and prepared dimensions for
successfully decoded images.
- Associate message images with their role and tool-output images with their
originating call ID.
- Include the collected image preparation metadata in the corresponding turn
analytics event.
## Testing
- Cover image resize metadata, tool-output attribution, turn aggregation, event
serialization, and app-server analytics output.
GitOrigin-RevId: dbfb5ba1ce7cb02dd93d9b579c5109817f16aef5