feat(erp): 添加本位币功能

- 新增 FunctionalCurrency 方法获取本位币信息
- 实现客户端调用逻辑
- 添加错误处理机制

erp/dict.go

@@ -104,3 +104,13 @@ func (d *dict) Delete(ctx context.Context, dictIds []int64) (err error) {
 	err = xClient.Call(ctx, "Delete", dictIds, &reply)
 	return
 }
+
+// FunctionalCurrency @TITLE 本位币
+func (d *dict) FunctionalCurrency(ctx context.Context) (reply DictItem, err error) {
+	xClient, err := client2.GetClient(d)
+	if err != nil {
+		return
+	}
+	err = xClient.Call(ctx, "FunctionalCurrency", 0, &reply)
+	return
+}