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, 47 insertions, 0 deletions

diff --git a/scripts/tests/test-fault.sh b/scripts/tests/test-fault.sh
new file mode 100755
index 0000000..0c39cde
--- /dev/null
+++ b/scripts/tests/test-fault.sh
@@ -0,0 +1,47 @@
+#!/usr/bin/env bash
+#
+# scripts/tests/test-fault.sh — fault-diagnostics verification.
+#
+# Proves the fault-dump path: every CPU exception prints a white-on-red
+# band to the framebuffer and a parseable serial line before halting.
+# Boots with a dedicated CRASHLOG FAT stick on ide.1 so the crash band
+# has somewhere to write.
+#
+# Usage: ./scripts/tests/test-fault.sh
+# Env:   SYSTEM_IMG, OVMF, QEMU (see scripts/lib.sh)
+#
+set -euo pipefail
+TNAME="fault"
+# shellcheck source=../lib.sh
+source "$(dirname "$0")/../lib.sh"
+
+echo "==> 1/5 build (kernel + bins)"
+build_all
+
+echo "==> 2/5 stage system image"
+stage_image --force
+
+echo "==> 3/5 boot QEMU (headless, + dedicated CRASHLOG stick)"
+CRASH_IMG=/tmp/rsdos-crash.img
+rm -f "$CRASH_IMG"
+mkfs.fat -C -F 32 -n CRASHLOG "$CRASH_IMG" 65536 >/dev/null
+test_boot \
+        -drive "file=$CRASH_IMG,format=raw,if=none,id=crash" \
+        -device ide-hd,drive=crash,bus=ide.1
+
+echo "==> 4/5 boot diagnostics present"
+grep -aq "gop: fb base=" "$LOG" || fail "fb geometry diagnostic missing"
+grep -aq "gop: mode .* selected" "$LOG" || fail "mode-selection diagnostic missing"
+grep -aq "CRASHLOG" "$LOG" || fail "CRASHLOG stick not mounted"
+
+echo "==> 5/5 inject a page fault (fault command)"
+sendkeys "clear" "fault"
+sleep 2
+
+grep -aq "!!! page fault vec=14 .*rip=" "$LOG" || fail "page-fault dump line missing"
+grep -aq "cr2=0x400000000000" "$LOG" || fail "CR2 not reported (faulting address)"
+grep -aq "task=0 \"shell\"" "$LOG" || fail "faulting task not identified"
+grep -aq "!!! halting" "$LOG" || fail "no halt message"
+
+echo ""
+echo "PASS — fault dump verified"