The lake was prod-stack-only; beta and LAN fell straight to NASA. Now the
compose stack gets the same service (backend image, THERMOGRAPH_ROLE=lake,
never host-published) and the backend points at it via THERMOGRAPH_LAKE_URL:
- deploy.sh rolls lake with every backend deploy (same image, different
role); deploy-stack.sh's backend leg updates it too, tolerating stacks
that predate the service.
- Creds: beta via the vault (added to beta.yaml); LAN via the Actions S3
secrets injected by backend-deploy-dev.yml (dev renders no vault). Without
creds the service stays healthy and answers 503 — reads fall through to
NASA, so a credential gap can never take a page down.
- Dev overlay lifts the CPU caps like every other service.
