refactor: 精简Azure OpenAI多分组功能实现

- 移除不必要的分组清理逻辑
- 简化组成员端点实现，使用简单的members.push()
- 移除OpenAI账户路由中的groupInfos添加
- 保持最小化修改原则，只保留必要的功能实现

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

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

src/services/geminiAccountService.js

@@ -585,10 +585,6 @@ async function deleteAccount(accountId) {
     throw new Error('Account not found')
   }
 
-  // 首先从所有分组中移除此账户
-  const accountGroupService = require('./accountGroupService')
-  await accountGroupService.removeAccountFromAllGroups(accountId)
-
   // 从 Redis 删除
   const client = redisClient.getClientSafe()
   await client.del(`${GEMINI_ACCOUNT_KEY_PREFIX}${accountId}`)

src/services/openaiAccountService.js

@@ -440,10 +440,6 @@ async function deleteAccount(accountId) {
     throw new Error('Account not found')
   }
 
-  // 首先从所有分组中移除此账户
-  const accountGroupService = require('./accountGroupService')
-  await accountGroupService.removeAccountFromAllGroups(accountId)
-
   // 从 Redis 删除
   const client = redisClient.getClientSafe()
   await client.del(`${OPENAI_ACCOUNT_KEY_PREFIX}${accountId}`)