feat: 添加账号异常状态 Webhook 通知功能

## 功能概述
- 新增账号禁用/异常状态的 Webhook 实时通知机制
- 支持 Claude OAuth、Claude Console、Gemini 三种平台的账号监控
- 提供完整的 Webhook 管理 API 和配置选项

## 主要变更

### 新增文件
- `src/utils/webhookNotifier.js`: Webhook 通知核心服务
- `src/routes/webhook.js`: Webhook 管理 API 路由

### 功能集成
- Claude OAuth 账号：unauthorized 状态 + token 刷新错误通知
- Claude Console 账号：blocked 状态通知
- Gemini 账号：token 刷新错误通知

### 配置支持
- 新增环境变量：WEBHOOK_ENABLED, WEBHOOK_URLS, WEBHOOK_TIMEOUT, WEBHOOK_RETRIES
- 支持多个 Webhook URL 并发通知
- 自动重试机制（指数退避）+ 超时保护

### 管理端点
- POST /admin/webhook/test: 测试连通性
- POST /admin/webhook/test-notification: 发送测试通知
- GET /admin/webhook/config: 查看配置信息

## 通知格式
```json
{
  "type": "account_anomaly",
  "data": {
    "accountId": "uuid",
    "accountName": "账号名称",
    "platform": "claude-oauth|claude-console|gemini",
    "status": "unauthorized|blocked|error",
    "errorCode": "CLAUDE_OAUTH_UNAUTHORIZED",
    "reason": "具体异常原因",
    "timestamp": "2025-01-13T10:30:00.000Z"
  }
}
```

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <noreply@anthropic.com>

src/services/claudeConsoleAccountService.js

@@ -395,6 +395,9 @@ class ClaudeConsoleAccountService {
     try {
       const client = redis.getClientSafe()
 
+      // 获取账户信息用于webhook通知
+      const accountData = await client.hgetall(`${this.ACCOUNT_KEY_PREFIX}${accountId}`)
+
       const updates = {
         status: 'blocked',
         errorMessage: reason,
@@ -404,6 +407,24 @@ class ClaudeConsoleAccountService {
       await client.hset(`${this.ACCOUNT_KEY_PREFIX}${accountId}`, updates)
 
       logger.warn(`🚫 Claude Console account blocked: ${accountId} - ${reason}`)
+
+      // 发送Webhook通知
+      if (accountData && Object.keys(accountData).length > 0) {
+        try {
+          const webhookNotifier = require('../utils/webhookNotifier')
+          await webhookNotifier.sendAccountAnomalyNotification({
+            accountId,
+            accountName: accountData.name || 'Unknown Account',
+            platform: 'claude-console',
+            status: 'blocked',
+            errorCode: 'CLAUDE_CONSOLE_BLOCKED',
+            reason: reason
+          })
+        } catch (webhookError) {
+          logger.error('Failed to send webhook notification:', webhookError)
+        }
+      }
+
       return { success: true }
     } catch (error) {
       logger.error(`❌ Failed to block Claude Console account: ${accountId}`, error)