[MASTER_PLAN.md §5 Phase 2]. Entry: Phase 1 green.
Exit gates:
storage-roundtrip: virtio-blk + VFS mount; ext2-class FS survives write→unmount→remount→fscknet-echo: un-stub netdev RX path (#28 S3); DHCP lease + TCP echo vs QEMU user-mode networkingfb-boot-log: full PSF font boot log (#27 S2); CI framebuffer screenshot artifact- ELF loader runs ≥10 coreutils from disk
Blocked by Phase 1 (#29... see umbrella list).