firmware.sh: if no local firmware-latest.fl, fetch https://zos.grid.tf/store/flists/firmware-latest.fl using wget or busybox wget; then mount via rfs. modules.sh: if no local modules-6.16.5-arch1-1.fl, fetch https://zos.grid.tf/store/flists/modules-6.16.5-arch1-1-Zero-OS.fl using wget or busybox wget; then mount via rfs. Keep env overrides MODULES_FLIST/FIRMWARE_FLIST and RFS_BIN semantics.