feat: room for many apps: qemu 512M, pool sized from RAM (448M, 114688 frames), user VA 32M -> 1G, display 8 windows (buffers at 0x1000_0000, stack 14 pages), pm app budget 24 MiB, init 16 children (notif bits moved)

scripts/test-qemu.sh

@@ -29,7 +29,7 @@ owner() {
 boot() {
     : > "${LOG}"; rm -f "${MON}"
     owner "$@" &
-    timeout ${QT:-120} qemu-system-riscv64 -machine virt -smp "${SMP}" -bios default \
+    timeout ${QT:-120} qemu-system-riscv64 -machine virt -m 512M -smp "${SMP}" -bios default \
         -kernel "${KERNEL}" \
         -drive "file=${IMAGE},if=none,format=raw,id=hd0" -device virtio-blk-device,drive=hd0 \
         -drive "file=${KEYS},if=none,format=raw,id=ks" -device virtio-blk-device,drive=ks \