added support for username variable for logging

scripts/Invoke-ReplaySave.ps1

@@ -21,7 +21,7 @@ if ($Port -eq 0) {
 
 # --- Start transcript logging ---
 try {
-    $logDir = Join-Path $config.LogPath $env:USERNAME
+    $logDir = [System.Environment]::ExpandEnvironmentVariables($config.LogPath)
     New-Item -ItemType Directory -Path $logDir -Force -ErrorAction SilentlyContinue | Out-Null
     Start-Transcript -Path (Join-Path $logDir 'OBSReplayBuffer-Save.log') -Append -ErrorAction Stop
 } catch {