fix: 创建缺失的E2E测试package.json文件

问题根本原因:
- CI配置执行 'cd e2e && npm ci'
- 但 e2e/package.json 文件不存在
- 导致npm ci命令失败，E2E测试无法执行

修复方案:
- 创建 e2e/package.json 文件
- 定义E2E测试所需依赖
- 配置测试脚本

验证:
- package.json语法正确
- 依赖版本与项目一致

Ralph Loop #4 完成

e2e/package.json

@@ -0,0 +1,15 @@
+{
+  "name": "novalon-website-e2e-tests",
+  "version": "1.0.0",
+  "private": true,
+  "scripts": {
+    "test": "playwright test",
+    "test:standard": "TEST_TIER=standard playwright test --config=playwright.config.tiered.ts",
+    "test:fast": "TEST_TIER=fast playwright test --config=playwright.config.tiered.ts",
+    "test:deep": "TEST_TIER=deep playwright test --config=playwright.config.tiered.ts"
+  },
+  "devDependencies": {
+    "@playwright/test": "^1.48.0",
+    "@types/node": "^20.0.0"
+  }
+}