Update project configuration and structure with Docker support and environment variable adjustments

- Updated .env.example to reflect new LLM configuration with Aliyun's API.
- Enhanced .gitignore to include additional files and directories for better exclusion of sensitive and build artifacts.
- Added docker-compose.yml for streamlined deployment of backend and frontend services.
- Introduced Dockerfiles for both backend and frontend to facilitate containerized builds.
- Created README.md to provide comprehensive project documentation and setup instructions.
- Established nginx configuration for frontend to support API proxying and static file serving.

frontend/Dockerfile

@@ -0,0 +1,34 @@
+# MiroFish Frontend Dockerfile
+# Multi-stage build: Node.js build + Nginx serve
+
+# ============= Build Stage =============
+FROM node:20-alpine as builder
+
+WORKDIR /app
+
+# 复制 package 文件
+COPY package*.json ./
+
+# 安装依赖
+RUN npm ci
+
+# 复制源代码
+COPY . .
+
+# 构建生产版本
+RUN npm run build
+
+# ============= Production Stage =============
+FROM nginx:alpine
+
+# 复制 Nginx 配置
+COPY nginx.conf /etc/nginx/conf.d/default.conf
+
+# 复制构建产物
+COPY --from=builder /app/dist /usr/share/nginx/html
+
+# 暴露端口
+EXPOSE 80
+
+# 启动 Nginx
+CMD ["nginx", "-g", "daemon off;"]