feat: 添加文件选择和自动查找功能，优化模板创建界面

src/renderer/store/template.ts

@@ -3,7 +3,8 @@ import { ref } from 'vue'
 
 interface TemplateFile {
   path: string
-  content: string
+  content?: string  // Content for text files that are created directly
+  sourceFilePath?: string  // Path to copy from for file copying
 }
 
 interface TemplateDirectory {