## What changed
- Add `suggestion_id` to plugin install elicitation metadata, using the same
value as the elicitation request ID and plugin-install analytics event.
- Leave connector install metadata unchanged by omitting the field.
## Testing
- Cover plugin and connector metadata serialization.
- Verify that remote plugin install metadata and analytics carry matching
suggestion IDs.
GitOrigin-RevId: 05dd1d210e2a82857094f09d27ecba79ee460b7e