MIL-013: Debian container and Windows Sandbox checks

A Debian image (python:3.13-slim-bookworm with Xvfb and GNOME's window
manager) runs the linters, the whole test suite, the screenshots and the
smoke test of a PyInstaller Linux binary and of the source program, so no
window opens on the development machine. The screenshot tool works on
Linux, a smoke driver presses the known button with the virtual mouse, and
Windows Sandbox scripts are written (not run, they open a window on the
host). README and the wiki Install pages describe it. Review records
RC-077 (Python) and RC-078 (shell).

Task: MIL-013#2
Task: MIL-013#3
Task: MIL-013#4
Task: MIL-013#5
Task: MIL-013#6
Task: MIL-013#7
Task: MIL-013#9
Task: MIL-013#10

tools/docker/smoke-binary.sh

@@ -0,0 +1,31 @@
+#!/usr/bin/env bash
+# Build the Linux binary with PyInstaller and smoke-test it, and the source
+# program, on the virtual desktop. The smoke test starts the program, finds the
+# window, presses the known button with the virtual mouse of the desktop and
+# checks the progress file.
+#
+# Purpose:  the "does the packaged program work" check without a desktop of the
+#           host (ADR-0005, RC-072).
+# Usage:    smoke-binary.sh [repeat-count]      (default 5)
+# Env:      see start-desktop.sh
+# Needs:    pyinstaller (the build extra), binutils, xdotool, the desktop
+# Exit:     0 only when every run of both programs passes; 2 on a bad count
+set -euo pipefail
+
+repeat="${1:-5}"
+if ! [[ "${repeat}" =~ ^[1-9][0-9]*$ ]]; then
+  echo "error: repeat-count must be a positive integer, got '${repeat}'" >&2
+  echo "usage: smoke-binary.sh [repeat-count]" >&2
+  exit 2
+fi
+
+cd "$(dirname "${BASH_SOURCE[0]}")/../.."
+# shellcheck source=tools/docker/start-desktop.sh
+. tools/docker/start-desktop.sh
+
+python tools/build_executable.py --clean
+test -x dist/flash-card
+echo "== binary"
+python tools/docker/smoke_driver.py --repeat "${repeat}" --command dist/flash-card
+echo "== source"
+python tools/docker/smoke_driver.py --repeat "${repeat}" --command python -m flash_card