feat: 使用 Playwright 实现自动化 cookie 获取和验证

主要变更:
- 新增 Playwright 登录认证服务 (services/playwright-auth.ts)
- 重构 get-activity.ts 使用 Playwright 替代 Axios 登录
- 实现自动 cookie 过期检测和重试机制
- 优化 Docker 配置支持 Playwright 浏览器运行
- 添加启动脚本自动验证和刷新 cookies
- 完善错误处理：区分 4xx(认证失败) 和 5xx(服务器错误)

技术细节:
- 删除旧版 login_template.txt 和 nkcs-engage.cookie.txt
- 添加 startup.sh 启动时自动验证 cookies
- 改进 cookie 验证逻辑，添加指数退避重试
- Dockerfile 安装 Playwright 系统依赖
- docker-compose.yaml 添加 volumes 和 health checks

测试:
- 添加 auth.spec.ts 自动化测试
- 添加 get-cookies.ts 和 test-cookies-validity.ts 工具脚本
- 验证 401/500/000 等错误场景处理正确

startup.sh

@@ -0,0 +1,25 @@
+#!/bin/sh
+set -e
+
+echo "🚀 Starting DSAS CCA Backend..."
+
+# Check if cookies exist and are valid
+if [ -f /usr/src/app/services/cookies.json ]; then
+  echo "📁 Cookies file found. Checking validity..."
+  
+  # Try to fetch a simple activity to test cookies
+  # If it fails, we'll get fresh cookies
+  if ! timeout 10 bun run test/test-cookies-validity.ts 2>/dev/null; then
+    echo "⚠️ Cookies are invalid or expired. Getting fresh cookies..."
+    bun run test/get-cookies.ts
+  else
+    echo "✅ Cookies are valid. Using cached cookies."
+  fi
+else
+  echo "📁 No cookies file found. Getting fresh cookies..."
+  bun run test/get-cookies.ts
+fi
+
+# Start the application
+echo "🎯 Starting application..."
+exec bun run index.ts