Long builds (NVIDIA driver download+compile) would abort on SSH timeout.
Now build runs in a detached screen session on the VM, run-builder.sh
streams the log and waits for completion safely.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
xz → lz4 for mksquashfs: kernel modloop rebuild is ~10x faster.
Size increase is acceptable since modloop is loaded into RAM.
Applied in both setup-builder.sh and build-debug.sh.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>