feat: Add Docker deployment support

- Updated Dockerfile to use npm instead of pnpm
- Added .dockerignore for optimized builds
- Created docker-compose.yml for easy deployment
- Added comprehensive Docker deployment guide
- Configured health checks and data persistence
- Ready for containerized deployment

Dockerfile

@@ -1,26 +1,23 @@
 # 使用官方Node.js运行时作为基础镜像
 FROM node:18-alpine
 
-# 安装pnpm
-RUN npm install -g pnpm@9.0.0
-
 # 设置工作目录
 WORKDIR /app
 
-# 复制package.json和pnpm-lock.yaml
-COPY package.json pnpm-lock.yaml ./
+# 复制package.json和package-lock.json
+COPY package.json package-lock.json ./
 
 # 安装所有依赖（包括开发依赖用于构建前端）
-RUN pnpm install --frozen-lockfile
+RUN npm ci
 
 # 复制应用代码
 COPY . .
 
 # 构建前端
-RUN pnpm run build
+RUN npm run build
 
 # 清理开发依赖，只保留生产依赖
-RUN pnpm install --frozen-lockfile --prod
+RUN npm ci --only=production
 
 # 创建数据目录用于SQLite数据库
 RUN mkdir -p /app/data