fix(micro-app): 修复 resolveType 调用不存在的 $A.platformType 报错

$A 上从未定义 platformType 方法,resolveType 解析微应用类型时
必抛 "$A.platformType is not a function"。改用既有 $A.Platform
属性判断桌面端(web/mac/win),保持 desktop/mobile 语义不变。

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

resources/assets/js/components/MicroApps/index.vue

@@ -801,7 +801,8 @@ export default {
                     ? type.mobile
                     : (typeof type.app === 'string' ? type.app : defaultType)
                 const desktopType = typeof type.desktop === 'string' ? type.desktop : defaultType
-                return $A.platformType() === 'desktop' ? desktopType : mobileType
+                const isDesktop = ['web', 'mac', 'win'].includes($A.Platform)
+                return isDesktop ? desktopType : mobileType
             }
             return 'inline'
         }