feat: 添加自动邮箱映射功能并完善署名系统

- 新增 attributionEmail.ts 实现模型名到邮箱的自动映射
- 重构署名逻辑，统一使用 getRealModelName() 和 getAttributionEmail()
- 将产品名从 Claude Code 更新为 Claude Code Best
- 更新 PRODUCT_URL 指向 claude-code-best fork 仓库

Co-Authored-By: glm-4.7 <noreply@zhipuai.cn>

src/utils/attributionEmail.ts

@@ -0,0 +1,22 @@
+const MODEL_EMAIL_MAP: Array<{ keywords: string[]; email: string }> = [
+  { keywords: ['claude'], email: 'noreply@anthropic.com' },
+  {
+    keywords: ['gpt', 'dall-e', 'o1-', 'o3-', 'o4-'],
+    email: 'noreply@openai.com',
+  },
+  { keywords: ['gemini'], email: 'noreply@google.com' },
+  { keywords: ['grok'], email: 'noreply@xai.com' },
+  { keywords: ['glm'], email: 'noreply@zhipuai.cn' },
+  { keywords: ['deepseek'], email: 'noreply@deepseek.com' },
+  { keywords: ['qwen'], email: 'noreply@alibabacloud.com' },
+]
+
+export function getAttributionEmail(modelName: string): string {
+  const lower = modelName.toLowerCase()
+  for (const { keywords, email } of MODEL_EMAIL_MAP) {
+    if (keywords.some(kw => lower.includes(kw))) {
+      return email
+    }
+  }
+  return 'noreply@anthropic.com'
+}