Initial commit: Go driver for the Lian Li Galahad II LCD

Streams H.264 to the Galahad II LCD via USB (gousb) with:
- ffmpeg CLI transcoding (no fragile FFmpeg C-ABI bindings)
- pure-Go Annex-B access-unit splitting
- framerate pacing with graceful shutdown and USB reconnect
- TOML config, cobra CLI, structured slog logging, unit tests

packaging/install.sh

@@ -0,0 +1,80 @@
+#!/usr/bin/env bash
+#
+# Install galahad2lcd: build, install the binary, systemd unit, udev rule
+# and (optionally) an initial configuration.
+#
+# Usage: sudo ./install.sh [/path/to/media.gif]
+
+set -euo pipefail
+
+APP=galahad2lcd
+BINDIR=/usr/local/bin
+SYSTEMD_DIR=/etc/systemd/system
+UDEV_DIR=/etc/udev/rules.d
+CONFIG_FILE=/etc/galahad2lcd.toml
+SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
+
+info()  { echo -e "\033[0;32m[+] $*\033[0m"; }
+warn()  { echo -e "\033[0;33m[!] $*\033[0m"; }
+fail()  { echo -e "\033[0;31m[-] $*\033[0m" >&2; exit 1; }
+
+[[ $EUID -eq 0 ]] || fail "run as root (sudo $0 $*)"
+
+if ! command -v go >/dev/null; then
+  fail "Go is required: sudo pacman -S go (or the equivalent for your distro)"
+fi
+
+info "building release binary"
+VERSION=$(git describe --tags --always --dirty 2>/dev/null || echo dev)
+go build -trimpath -ldflags "-s -w -X main.version=${VERSION}" -o "${BINDIR}/${APP}" \
+  "${SCRIPT_DIR}/../cmd/galahad2lcd"
+
+info "installing systemd unit"
+install -m 0644 "${SCRIPT_DIR}/${APP}.service" "${SYSTEMD_DIR}/${APP}.service"
+
+info "installing udev rule"
+install -m 0644 "${SCRIPT_DIR}/99-${APP}.rules" "${UDEV_DIR}/99-${APP}.rules"
+udevadm control --reload-rules 2>/dev/null || true
+
+# Remove the legacy Rust-driver config file (/etc/default/galahad2lcd) if
+# present; the new driver uses /etc/galahad2lcd.toml.
+rm -f /etc/default/${APP}
+
+if [[ ! -f "${CONFIG_FILE}" ]]; then
+  if [[ $# -ge 1 ]]; then
+    INPUT="$(realpath "$1")"
+    [[ -f "$INPUT" ]] || fail "file '$INPUT' does not exist"
+    info "writing initial configuration for $INPUT"
+    cat > "${CONFIG_FILE}" <<EOF
+[display]
+input = "${INPUT}"
+rotate = 0
+speed = 1.0
+
+[usb]
+vendor_id = 0x0416
+product_id = 0x7395
+
+[stream]
+fps = 0
+cache_path = "/tmp/galahad_cache.h264"
+EOF
+  else
+    warn "no media file given; run 'sudo ${APP} set --input /path/to/media.gif' after install"
+  fi
+fi
+chmod 0644 "${CONFIG_FILE}"
+
+info "reloading systemd and starting ${APP}"
+systemctl daemon-reload
+systemctl enable "${APP}"
+systemctl restart "${APP}"
+
+info "installation complete"
+echo
+echo "  Change the media later with:"
+echo "    sudo ${APP} set --input /path/to/media.gif --rotate 0"
+echo "  Inspect USB devices with:"
+echo "    ${APP} list"
+echo "  View logs with:"
+echo "    journalctl -u ${APP} -f"