scripts: rebuild the dev loop around build.sh/run.sh

`make` did not parse at all (missing separator at line 139), so every
make target was dead.  The folder also carried three overlapping
launchers (boot.sh, qemu.sh, boot-image.sh) plus a fourth partial one
in the Makefile, `cargo build --package rsdos` copy-pasted eight times,
the QEMU invocation copy-pasted per script, and the test helpers
(fail/wait_log/wait_qemu_exit/qemu_hmp) duplicated in five tests.

New layout:
- scripts/lib.sh: single config (image, OVMF, mem/smp), the one cargo
  invocation (build_all), the one QEMU shape (qemu_args), and the test
  harness (test_boot, wait_log, wait_qemu_exit, qemu_hmp, sendkeys)
- scripts/build.sh: kernel + every bins/* in one pass
- scripts/mksystem.sh: freshness-aware image build that now stages
  every bins/*.efi into /bin/cli|gui (they were never copied before)
- scripts/run.sh: build + stage + boot in one command; --headless,
  --debug (GDB stub), --monitor (HMP socket), --fresh, --mem/--smp/
  --bios/--image; on Wayland it auto-selects XWayland plus
  grab-on-hover so the mouse can be captured (Ctrl+Alt+G toggles)
- scripts/tests/: the five automated tests on the shared harness
- deleted: boot.sh, qemu.sh, boot-image.sh, lib-boot-args.sh,
  build-image-release.sh, build-bootloader.sh (rsboot chain dropped)

The Makefile is now a thin wrapper: make run, make test, make system,
make inspect, make help.  Two-command flow: ./scripts/build.sh then
./scripts/run.sh (run.sh alone also works).

Stale test assumptions fixed so the suite is green again: test-gfx
waited for "gfx: check" while the shell prints "gfx check: PASS";
test-mouse/test-msg hardcoded msgrecv = task 3 (wm-input took slot 3 —
ids are parsed from the log now); the queue-full probe targeted task 0,
whose exec pump drains its own queue as completion codes (moved to the
cursor task, which never recvs).

Verified in QEMU: make test -> test-disk, test-gfx, test-mouse,
test-msg, test-fault all PASS.

1 files changed, 67 insertions, 0 deletions

diff --git a/scripts/tests/test-disk.sh b/scripts/tests/test-disk.sh
new file mode 100755
index 0000000..3836b6d
--- /dev/null
+++ b/scripts/tests/test-disk.sh
@@ -0,0 +1,67 @@
+#!/usr/bin/env bash
+#
+# scripts/tests/test-disk.sh — full automated data-disk round trip.
+#
+# Builds, stages the system image, boots QEMU headless, drives the shell
+# via the monitor (ls / mkdir / echo WRITING / cat / poweroff), then
+# verifies the results with mtools and fsck.
+#
+# Usage:
+#   ./scripts/tests/test-disk.sh            reuse the existing image
+#   ./scripts/tests/test-disk.sh --fresh    reformat + reseed first
+#
+# Env: SYSTEM_IMG, OVMF, QEMU (see scripts/lib.sh)
+#
+set -euo pipefail
+TNAME="disk"
+# shellcheck source=../lib.sh
+source "$(dirname "$0")/../lib.sh"
+
+FRESH=0
+[ "${1:-}" = "--fresh" ] && FRESH=1
+STAMP="$(date +%s)"
+
+echo "==> 1/6 build (kernel + bins)"
+build_all
+
+echo "==> 2/6 stage system image"
+if [ "$FRESH" -eq 1 ]; then stage_image --force; else stage_image; fi
+
+echo "==> 3/6 boot QEMU (headless)"
+test_boot
+sleep 1
+
+# Volumes mount under /disk/<UID>/ where UID = "LABEL-SERIAL" (e.g.
+# RSDOS-5BD1E55F).  Discover it from the boot log so the test works on
+# any image without knowing the serial in advance.
+VOL_UID="$(grep -a 'fat: mounted' "$LOG" | sed -n 's/.*at \/disk\/\([^ )]*\).*/\1/p' | head -1)"
+[ -n "$VOL_UID" ] || fail "no FAT32 volume was mounted (look for 'fat: mounted' in the log)"
+echo "  mounted volume UID: $VOL_UID"
+
+echo "==> 4/6 drive the shell (ls / mkdir / echo WRITING / cat / poweroff)"
+# The filename is deliberately >13 chars so the FAT LFN path gets
+# multi-entry entries (they're stored last-first on disk).
+TESTFILE="disk-test-$STAMP.txt"
+sendkeys \
+        "ls /disk" \
+        "mkdir /disk/$VOL_UID/sub" \
+        "echo disk-test-$STAMP WRITING /disk/$VOL_UID/sub/$TESTFILE" \
+        "cat /disk/$VOL_UID/sub/$TESTFILE" \
+        "poweroff"
+
+echo "==> 5/6 wait for shutdown"
+wait_qemu_exit 30 || fail "QEMU did not exit after poweroff"
+
+echo "==> 6/6 verify"
+grep -a "disk-test-$STAMP" "$LOG" >/dev/null || fail "cat output missing from serial log"
+if ! fsck.fat -n "$SYSTEM_IMG" >/tmp/rsdos-fsck.out 2>&1; then
+        fail "fsck.fat reports problems: $(tail -3 /tmp/rsdos-fsck.out)"
+fi
+MT="$(mtype -i "$SYSTEM_IMG" "::/sub/$TESTFILE" 2>/dev/null || true)"
+[ "$MT" = "disk-test-$STAMP" ] || fail "mtype mismatch: got '$MT'"
+
+echo ""
+echo "PASS — disk round trip OK (fsck clean, file survived poweroff)"
+echo "  image:      $SYSTEM_IMG"
+echo "  volume:     /disk/$VOL_UID"
+echo "  written:    /disk/$VOL_UID/sub/$TESTFILE = \"disk-test-$STAMP\""