build: 更新版本号至1.0.18+54并添加应用内购买插件依赖

添加in_app_purchase插件依赖以支持应用内购买功能

pubspec.yaml

@@ -1,7 +1,7 @@
 name: voitrans
 description: "Voitrans - AI Voice Assistant."
 publish_to: "none"
-version: 1.0.18+53
+version: 1.0.18+54
 
 environment:
   sdk: ">=3.3.0 <4.0.0"
@@ -113,6 +113,7 @@ dependencies:
     path: local_plugins/qq_music
   test:
     path: local_plugins/test
+  in_app_purchase: ^3.2.3 # 应用内购买插件
 
 dev_dependencies:
   flutter_test: