支持联系人签名、标签分组、地区获取；优化导出效果

src/types/electron.d.ts

@@ -219,7 +219,7 @@ export interface ElectronAPI {
     updateMessage: (sessionId: string, localId: number, createTime: number, newContent: string) => Promise<{ success: boolean; error?: string }>
     deleteMessage: (sessionId: string, localId: number, createTime: number, dbPathHint?: string) => Promise<{ success: boolean; error?: string }>
     resolveTransferDisplayNames: (chatroomId: string, payerUsername: string, receiverUsername: string) => Promise<{ payerName: string; receiverName: string }>
-    getContacts: () => Promise<{
+    getContacts: (options?: { lite?: boolean }) => Promise<{
       success: boolean
       contacts?: ContactInfo[]
       error?: string

src/types/models.ts

@@ -39,6 +39,7 @@ export interface ContactInfo {
   alias?: string
   labels?: string[]
   detailDescription?: string
+  region?: string
   avatarUrl?: string
   type: 'friend' | 'group' | 'official' | 'former_friend' | 'other'
 }