优化导出速度，提供可选项优化

src/types/electron.d.ts

@@ -852,6 +852,7 @@ export interface ExportOptions {
   sessionNameWithTypePrefix?: boolean
   displayNamePreference?: 'group-nickname' | 'remark' | 'nickname'
   exportConcurrency?: number
+  imageDeepSearchOnMiss?: boolean
 }
 
 export interface ExportProgress {