chore(studio): wire deployment health compose baseline

[man4ish]

Summary

Provides the runtime configuration Control Center's new Deployment
Health feature (see OmniBioAI/omnibioai-control-center#61) needs to
read this repository's own Compose file as its authoritative deployment
baseline.

Adds three environment variables to control-center's existing
environment: block:

DEPLOYMENT_HEALTH_COMPOSE_PATH: /workspace/omnibioai-studio/docker-compose.yml
DEPLOYMENT_HEALTH_BASELINE_SOURCE: development
DEPLOYMENT_HEALTH_DEPLOYMENT_REPOSITORY: omnibioai-studio

What this does not do

• No new mount. ${MACHINE_DIR}:/workspace already makes this exact
  file readable inside the control-center container, for unrelated,
  pre-existing reasons -- this change only points the new feature's
  parser at a path that was already reachable.
• No secret configuration added.
• No Docker Socket Proxy policy changed -- control-center's
  DOCKER_HOST already went through the proxy before this change.
• No unrelated Studio changes. This is a single 10-line hunk in one
  file; nothing else in this repository is touched.

Why development, not release

Confirmed by reading the actually-running deployment's own
com.docker.compose.project.config_files label: this file, alone, with
no overlay, is what actually produced the running stack.

Verification

• docker compose config --quiet: valid
• git diff --check: clean
• Live-verified against the deployed omnibioai-control-center
  backend during that repo's DH-4 certification (all fixture testing
  used safe, single-service, fully-reversible mechanisms -- no other
  service was ever stopped or restarted; see
  docs/DEPLOYMENT_HEALTH_DH4.md in the Control Center PR for the full
  record)

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