chore: 框架科学优化前的完整基线

在开始'设备契约层 + 目录重构 + 通止规装配'改造之前，先钉住当前可运行状态，
使后续任何删除/重构都可回退。

本基线包含：
- 现有 ROS 2 工作区全部源码（arm_application / arm_control / arm_bringup 等）
- 官方 flexiv_ros2 栈（含 flexiv_hardware / flexiv_controllers 等符号链接）
- 设备契约层 src/arm_interfaces（新增，46 项单测通过）
- devices/ 设备选型与品牌清单（新增）
- scripts/gen_site_example.py 与由它生成的 config/site.example.yaml

按 .gitignore 排除：build/ / install/ / log/ / config/site.yaml / 模型权重二进制。

scripts/check_robot_network.sh

@@ -0,0 +1,90 @@
+#!/usr/bin/env bash
+# Check PC ↔ Flexiv robot network (addresses from site.yaml)
+set -euo pipefail
+
+ROOT="$(cd "$(dirname "${BASH_SOURCE[0]}")/.." && pwd)"
+# shellcheck disable=SC1091
+source "${ROOT}/scripts/lib/load_site_config.sh" 2>/dev/null || true
+
+ROBOT_IP="${ROBOT_IP:-${SITE_ROBOT_IP:-192.168.100.1}}"
+ROBOT_SN="${ROBOT_SN:-${SITE_ROBOT_SN:-Rizon4-063989}}"
+PC_IP="${PC_IP:-${SITE_PC_IP:-192.168.100.10}}"
+
+pick_iface() {
+  if [[ -n "${IFACE:-}" ]]; then
+    echo "$IFACE"
+    return
+  fi
+  if [[ -n "${SITE_NET_IFACE:-}" && -d "/sys/class/net/${SITE_NET_IFACE}" ]]; then
+    echo "${SITE_NET_IFACE}"
+    return
+  fi
+  local d
+  for d in enp4s0 enp5s0 eth0; do
+    [[ -d /sys/class/net/$d ]] && echo "$d" && return
+  done
+  for d in $(ls /sys/class/net); do
+    [[ "$d" == lo ]] && continue
+    [[ "$d" == en* || "$d" == eth* ]] || continue
+    local state
+    state=$(cat /sys/class/net/"$d"/operstate 2>/dev/null || echo down)
+    [[ "$state" == up ]] && echo "$d" && return
+  done
+  echo enp4s0
+}
+
+IFACE="$(pick_iface)"
+
+echo "=== 本机网卡 ==="
+ip -4 -br addr
+
+echo
+echo "=== 目标机器人（site.yaml） ==="
+echo "  SN     $ROBOT_SN"
+echo "  标签   ${SITE_ROBOT_LABEL:-}"
+echo "  目录   ${SITE_ROBOT_CATALOG:-}"
+echo "  IP     $ROBOT_IP"
+echo "  本机   $PC_IP"
+echo "  网卡   $IFACE"
+if ping -c 1 -W 1 "$ROBOT_IP" >/dev/null 2>&1; then
+  echo "  ping UP — 链路 OK"
+else
+  echo "  ping DOWN — PC 与机器人必须同网段（本机 ${PC_IP} ↔ 机器人 ${ROBOT_IP}）"
+  echo
+  echo "  一键修复（交换机 / 有线）："
+  echo "    bash ~/ros2/scripts/fix_robot_lan.sh"
+  echo "  独立交换机（不要办公网 DHCP）可用："
+  echo "    bash ~/ros2/scripts/fix_robot_lan.sh --only"
+fi
+
+echo
+echo "=== 常见地址探测 ==="
+CANDIDATES=(
+  "$ROBOT_IP"
+  192.168.2.100 192.168.2.10 192.168.101.1 192.168.101.10
+  192.168.100.1 192.168.100.10
+  192.168.100.1 192.168.100.2 192.168.100.10
+  192.168.1.1
+)
+seen=""
+for ip in "${CANDIDATES[@]}"; do
+  [[ " ${seen} " == *" ${ip} "* ]] && continue
+  seen+=" ${ip}"
+  if ping -c 1 -W 1 "$ip" >/dev/null 2>&1; then
+    echo "  UP   $ip"
+  else
+    echo "  down $ip"
+  fi
+done
+
+echo
+echo "=== 当前邻居 (ARP) ==="
+ip neigh | grep -v FAILED || true
+
+echo
+echo "说明："
+echo "1) 网线接机器人控制柜网口 ↔ 本机 $IFACE。"
+echo "2) 示教器开启 RDK / 远程控制后再连。"
+echo "3) RDK 连接用 SN（不是 IP）：flexivrdk.Robot('$ROBOT_SN')"
+echo "4) 切换机械臂：改 ~/ros2/config/site.yaml 的 robot.sn"
+echo "5) 手册: https://flexiv.cn/software/rdk/manual/index.html"