The final "UPDATE executions SET result=$::jsonb" built its payload with
fmt.Sprintf and only escaped newlines. apt/pct output contains quotes,
backslashes and control chars, so the payload was invalid JSON, the jsonb
cast failed, and the (unchecked) UPDATE was silently discarded — the
execution stayed 'approved' with a NULL result even though the LXC was fully
provisioned (verified live: vmid auto-assigned, container running, service
installed, post_install ran).
- executeApprovedAction: marshal result via json.Marshal; log UPDATE errors
- add jsonErr() helper; route all pct_create failure-path results through it
- mcp/server.go: add jsonOut() for restart/systemctl/pct_exec inline results
- regression test for JSON validity on quote/backslash/control-char output
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
dtoro
a1f666f68a