feat(transfer): swap source and target connections

apps/desktop/src/components/transfer/DataTransferDialog.vue

@@ -651,6 +651,88 @@ function resetState(cancelTaskLoad = true) {
   savedConfigSnapshot.value = "";
 }
 
+/**
+ * 交换源和目标两侧：连接、Catalog、数据库、Schema 的选择随各自一侧整体互换，
+ * 一次点击即可反转传输方向。对象树只属于源端，旧选择作废，按新源端重新加载。
+ */
+function swapSourceAndTarget() {
+  const sourceState = {
+    connectionId: sourceConnectionId.value,
+    catalog: sourceCatalog.value,
+    catalogs: sourceCatalogs.value,
+    database: sourceDatabase.value,
+    databases: sourceDatabases.value,
+    schema: sourceSchema.value,
+    schemas: sourceSchemas.value,
+  };
+  const targetState = {
+    connectionId: targetConnectionId.value,
+    catalog: targetCatalog.value,
+    catalogs: targetCatalogs.value,
+    database: targetDatabase.value,
+    databases: targetDatabases.value,
+    schema: targetSchema.value,
+    schemas: targetSchemas.value,
+  };
+
+  if (sourceState.connectionId === targetState.connectionId && sourceState.catalog === targetState.catalog && sourceState.database === targetState.database && sourceState.schema === targetState.schema) {
+    // 两侧选择完全相同（含都未选择）时交换没有意义
+    return;
+  }
+
+  // 若正在加载已保存任务，先取消，避免任务加载链覆盖交换后的状态
+  taskLoadTracker.cancel();
+  pendingSourceSchemaPrefill.value = "";
+  pendingTargetSchemaPrefill.value = "";
+  pendingSelectedTablesPrefill.value = null;
+  pendingSelectedObjectsPrefill.value = null;
+
+  // 只在值确实变化时设置一次性跳过标记：标记由对应 watcher 消费，
+  // 若值未变则 watcher 不会触发，残留标记会误吞后续一次真实变更。
+  if (sourceConnectionId.value !== targetState.connectionId) {
+    skipSourceWatch.value = true;
+    sourceConnectionId.value = targetState.connectionId;
+  }
+  if (sourceCatalog.value !== targetState.catalog) {
+    skipSourceCatalogWatch.value = true;
+    sourceCatalog.value = targetState.catalog;
+  }
+  sourceCatalogs.value = targetState.catalogs;
+  if (sourceDatabase.value !== targetState.database) {
+    skipSourceDatabaseWatch.value = true;
+    sourceDatabase.value = targetState.database;
+  }
+  sourceDatabases.value = targetState.databases;
+  if (sourceSchema.value !== targetState.schema) {
+    skipSourceSchemaWatch.value = true;
+    sourceSchema.value = targetState.schema;
+  }
+  sourceSchemas.value = targetState.schemas;
+
+  if (targetConnectionId.value !== sourceState.connectionId) {
+    skipTargetWatch.value = true;
+    targetConnectionId.value = sourceState.connectionId;
+  }
+  if (targetCatalog.value !== sourceState.catalog) {
+    skipTargetCatalogWatch.value = true;
+    targetCatalog.value = sourceState.catalog;
+  }
+  targetCatalogs.value = sourceState.catalogs;
+  if (targetDatabase.value !== sourceState.database) {
+    skipTargetDatabaseWatch.value = true;
+    targetDatabase.value = sourceState.database;
+  }
+  targetDatabases.value = sourceState.databases;
+  targetSchema.value = sourceState.schema;
+  targetSchemas.value = sourceState.schemas;
+
+  // 对象树始终跟随源端：新源端是旧目标端，旧选择已无意义，清空后重新加载
+  objectGroups.value = {};
+  selectedObjects.value = {};
+  objectSearch.value = "";
+  void loadObjects();
+}
+
 async function startTransfer() {
   if (!canStart.value || isSubmitting.value) return;
   isSubmitting.value = true;
@@ -1037,9 +1119,11 @@ async function saveConfigTask() {
                 </div>
               </div>
 
-              <!-- Arrow -->
+              <!-- Swap source / target -->
               <div class="flex items-center pt-8">
-                <ArrowLeftRight class="w-5 h-5 text-muted-foreground" />
+                <Button variant="ghost" size="icon" class="h-7 w-7" :title="t('transfer.swap')" :aria-label="t('transfer.swap')" @click="swapSourceAndTarget">
+                  <ArrowLeftRight class="w-3.5 h-3.5" />
+                </Button>
               </div>
 
               <!-- Target Section -->

apps/desktop/src/i18n/locales/en.ts

@@ -5219,6 +5219,7 @@ export default {
     searchCatalog: "Search catalog...",
     sourceDatabase: "Source Database",
     sourceSchema: "Source Schema",
+    swap: "Swap source and target",
     targetConnection: "Target Connection",
     targetDatabase: "Target Database",
     targetSchema: "Target Schema",

apps/desktop/src/i18n/locales/es.ts

@@ -5014,6 +5014,7 @@ export default withEnglishFallback({
     overallProgress: "Progreso general",
     dataTransfer: "Transferencia de datos",
     sourceSchema: "Esquema de origen",
+    swap: "Intercambiar origen y destino",
     targetSchema: "Esquema de destino",
     runInBackground: "Ejecutar en segundo plano",
     newTask: "Nueva transferencia",

apps/desktop/src/i18n/locales/it.ts

@@ -4977,6 +4977,7 @@ export default withEnglishFallback({
     sourceConnection: "Connessione Sorgente",
     sourceDatabase: "Database Sorgente",
     sourceSchema: "Schema Sorgente",
+    swap: "Inverti sorgente e destinazione",
     targetConnection: "Connessione Destinazione",
     targetDatabase: "Database Destinazione",
     targetSchema: "Schema Destinazione",

apps/desktop/src/i18n/locales/ja.ts

@@ -5006,6 +5006,7 @@ export default withEnglishFallback({
     sourceConnection: "ソース接続",
     sourceDatabase: "ソースデータベース",
     sourceSchema: "ソーススキーマ",
+    swap: "ソースとターゲットを入れ替え",
     targetConnection: "ターゲット接続",
     targetDatabase: "ターゲットデータベース",
     targetSchema: "ターゲットスキーマ",

apps/desktop/src/i18n/locales/ko.ts

@@ -4644,6 +4644,7 @@ export default withEnglishFallback({
     sourceConnection: "소스 연결",
     sourceDatabase: "소스 데이터베이스",
     sourceSchema: "소스 스키마",
+    swap: "소스와 대상 교체",
     targetConnection: "대상 연결",
     targetDatabase: "대상 데이터베이스",
     targetSchema: "대상 스키마",

apps/desktop/src/i18n/locales/pt-BR.ts

@@ -4979,6 +4979,7 @@ export default withEnglishFallback({
     sourceConnection: "Conexão de origem",
     sourceDatabase: "Banco de dados de origem",
     sourceSchema: "Schema de origem",
+    swap: "Trocar origem e destino",
     targetConnection: "Conexão de destino",
     targetDatabase: "Banco de dados de destino",
     targetSchema: "Schema de destino",

apps/desktop/src/i18n/locales/zh-CN.ts

@@ -5204,6 +5204,7 @@ export default withEnglishFallback({
     searchCatalog: "搜索 Catalog...",
     sourceDatabase: "源数据库",
     sourceSchema: "源 Schema",
+    swap: "交换源和目标",
     targetConnection: "目标连接",
     targetDatabase: "目标数据库",
     targetSchema: "目标 Schema",

apps/desktop/src/i18n/locales/zh-TW.ts

@@ -4303,6 +4303,7 @@ export default withEnglishFallback({
     sourceConnection: "來源連線",
     sourceDatabase: "來源資料庫",
     sourceSchema: "來源 Schema",
+    swap: "交換來源與目標",
     targetConnection: "目標連線",
     targetDatabase: "目標資料庫",
     targetSchema: "目標 Schema",