chore: 删除未使用代码 (#37)

src/api/index.ts

@@ -1,8 +1,6 @@
 import type { GenericAbortSignal } from 'axios'
 import { post } from '@/utils/request'
 
-export const controller = new AbortController()
-
 export function fetchChatAPI<T = any>(
   prompt: string,
   options?: { conversationId?: string; parentMessageId?: string },