Live deploy console: stream compose up output to the browser (0.22.0)

Deploying a local stack from the editor now opens a console modal that streams
the `docker compose up -d` output (image pulls, container creation) live over a
new `/ws/deploy/{stack_id}` WebSocket, replacing the blind "Deploying…" spinner.
The compose subprocess keeps running server-side if the modal is closed early;
the same audit entry + start/error notification as the REST start path is recorded.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

backend/agent_app.py

@@ -62,7 +62,7 @@ def _map_docker(exc: DockerError):
         raise HTTPException(status_code=code, detail=exc.detail or exc.error)
     raise exc  # falls through to the global 502 DockerError handler
 
-AGENT_VERSION = "0.21.6"
+AGENT_VERSION = "0.22.0"
 
 
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