raise zlay memory limit from 3Gi to 4Gi for ReleaseSafe
debug build steady-state is ~1.6 GiB. ReleaseSafe hit the 3 GiB
cgroup limit during startup within 22 seconds. 4 GiB gives headroom
for ReleaseSafe's larger stack frames and inline expansion.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>