conleche-nightly red on intel-clean-room: hard-coded CI_CACHE under root-owned /mnt/nvme-raid0 #4758

conleche-nightly failed 2026-10-03 and 2026-10-04 (run 37163229207) on runner intel-clean-room with mkdir: cannot create directory '/mnt/nvme-raid0/ci-cache': Permission denied. /mnt/nvme-raid0 is root:root 755 on that host and the runner user is noah, so the job never reached a con-leche verdict.

Fix: put CI_CACHE under the runner user's $HOME/.cache/pvl-conleche, the same root conleche.sh defaults to. Every step and verdict class is unchanged.