Refactor project structure by removing Docker support and updating environment configuration

- Deleted docker-compose.yml, backend Dockerfile, frontend Dockerfile, and nginx configuration to streamline project setup.
- Updated .env.example to reorganize LLM and ZEP API configurations for clarity and ease of use.
- Enhanced README.md to reflect changes in project structure and provide clearer setup instructions.

frontend/Dockerfile

@@ -1,34 +0,0 @@
-# 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;"]

frontend/nginx.conf

@@ -1,45 +0,0 @@
-server {
-    listen 80;
-    server_name localhost;
-    root /usr/share/nginx/html;
-    index index.html;
-
-    # Gzip 压缩
-    gzip on;
-    gzip_types text/plain text/css application/json application/javascript text/xml application/xml;
-    gzip_min_length 1000;
-
-    # Vue Router history 模式支持
-    location / {
-        try_files $uri $uri/ /index.html;
-    }
-
-    # API 代理到后端
-    location /api/ {
-        proxy_pass http://backend:5001;
-        proxy_http_version 1.1;
-        proxy_set_header Upgrade $http_upgrade;
-        proxy_set_header Connection 'upgrade';
-        proxy_set_header Host $host;
-        proxy_set_header X-Real-IP $remote_addr;
-        proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
-        proxy_set_header X-Forwarded-Proto $scheme;
-        proxy_cache_bypass $http_upgrade;
-        
-        # 超时设置（模拟可能耗时较长）
-        proxy_connect_timeout 60s;
-        proxy_send_timeout 300s;
-        proxy_read_timeout 300s;
-    }
-
-    # 健康检查代理
-    location /health {
-        proxy_pass http://backend:5001/health;
-    }
-
-    # 静态文件缓存
-    location ~* \.(js|css|png|jpg|jpeg|gif|ico|svg|woff|woff2)$ {
-        expires 1y;
-        add_header Cache-Control "public, immutable";
-    }
-}