Add support for temperature background scans

Currently only room temperature background scans is supported. We need to be able to do background scans at different temperatures and store this information in the scan metadata.

## Acceptance Criteria
- A temperature background scan can be queued by the i15-1 plugin when needed

Start in the i15-1 plugin at the existing room-temperature background scan queueing path, then trace how scan metadata is represented and stored. Done means the plugin can queue a background scan at a requested temperature and that temperature is retained in the scan metadata; the issue names no tests or files, so identify the relevant ones while tracing the current flow.

Written by the indexing model from the issue text.