pipeline inefficiency (DEV/QAS/PRD) with no automated snapshot taken in between

### Description

I would like to be able to take an automated snapshot after deployment of a pipeline to a device.

Currently if i want a pipeline: DEV/QAS/PROD i have to toggle QAS fleet > dev > fleet to push my version onwards to PROD.

If an automatic snapshot could be taken automatically after deployment of DEV>QAS pipeline in the QAS device i dont have to do this unneeded toggling.

This is not a functional issue, just a hassle to do every time.

### Which customers would this be available to

Everyone - CE/Starter/Team/Enterprise

### Have you provided an initial effort estimate for this issue?

I am not a FlowFuse team member

No files, tests, or entry points are named. Start by tracing how DEVQAS pipeline deployments reach the QAS device and how snapshots are created or promoted; done means a snapshot is taken automatically after deployment so the fleet no longer needs to be toggled manually.

Written by the indexing model from the issue text.