重构后端，改为 node 技术栈

backend/stop.sh

@@ -0,0 +1,13 @@
+#!/bin/bash
+echo "Stopping Audio Dashboard API..."
+
+# 查找占用 8083 端口的进程
+PID=$(lsof -ti :8083 2>/dev/null)
+
+if [ -n "$PID" ]; then
+    echo "Found process PID: $PID"
+    kill -9 "$PID" 2>/dev/null
+    echo "Service stopped."
+else
+    echo "No service running on port 8083."
+fi