Update README and project cleanup

start.command

@@ -0,0 +1,24 @@
+#!/bin/bash
+cd "$(dirname "$0")"
+echo "[DMP] 正在启动系统..."
+
+if ! command -v node &> /dev/null
+then
+    echo "[ERROR] 未找到 Node.js，请从 https://nodejs.org 安装"
+    exit
+fi
+
+if [ ! -d "node_modules" ]; then
+    echo "[DMP] 正在安装依赖..."
+    npm install
+fi
+
+if [ ! -f "dmp_onion.db" ]; then
+    echo "[DMP] 正在初始化演示数据库..."
+    node db/seed.js
+    node db/seed_openai.js
+fi
+
+echo "[DMP] 启动服务器..."
+open "http://localhost:3456"
+node server.js