97a1ad301f
test-usb-storage-qemu.sh:
- Require [PASS] STORAGE_WRITE + STORAGE_READBACK + STORAGE_RESTORE
(previously only checked STORAGE_READBACK)
- Expect each check individually, fail fast on any FAIL
USB-IMPLEMENTATION-PLAN.md v2:
- P0-A4: marked done (bounds check committed)
- P2-A: marked done (write+readback proof already in checker)