Supabase free-tier cold-starts can push `gbrain sources list --json` past
10s (observed 14.5s in the wild), causing probeSource() to throw ETIMEDOUT
during /sync-gbrain code stage even though the underlying CLI was healthy.
Matches the 30s ceiling already used by `sources add` / `sources remove`
in the same file.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
