chore: 修复大量导入路径错误

- 迁移 files API 到 shared/api/
- 修复所有 features 中的 @/api/ 导入
- 修复所有 features 中的 @/composables/ 导入
- 更新 useOrderDetail 中的 uploadFile 调用

类型错误：272 → 190 → 135

frontend/src/features/chats/views/MessagesView.vue

@@ -3,8 +3,8 @@ import { computed, onMounted, ref } from 'vue'
 import { useRouter } from 'vue-router'
 import { ElMessage } from 'element-plus'
 import { ChatDotRound, Refresh, Tickets } from '@element-plus/icons-vue'
-import { fetchChats, type ChatConversation } from '@/api/chats'
-import { useChatSSE, type ChatEvent } from '@/composables/useChatSSE'
+import { fetchChats, type ChatConversation } from '@/features/chats/api/chats'
+import { useChatSSE, type ChatEvent } from '@/features/chats/composables/useChatSSE'
 import { formatDateMinute } from '@/utils/time'
 
 const router = useRouter()