fix(test): preserve singleton lifecycle samples

Keep one-item endpoint and checkpoint results as arrays under PowerShell strict mode so the uncapped reconnect session is validated by the same gate as the multi-checkpoint capped route.

tools/run-connected-world-lifecycle-gate.ps1

@@ -219,11 +219,12 @@ function Invoke-Session(
             -RedirectStandardOutput $stdout -RedirectStandardError $stderr -PassThru
         Wait-ForPattern $client $stdout '[UI-PROBE] UI probe script complete' $SessionTimeoutSeconds
 
-        $clientPort = @(Get-NetUDPEndpoint -OwningProcess $client.Id -ErrorAction SilentlyContinue |
+        $clientPorts = @(Get-NetUDPEndpoint -OwningProcess $client.Id -ErrorAction SilentlyContinue |
             Select-Object -First 1 -ExpandProperty LocalPort)
-        if ($clientPort.Count -ne 1) {
+        if ($clientPorts.Count -ne 1) {
             throw "could not resolve the client's UDP endpoint for ACE disconnect verification"
         }
+        $clientPort = [int]$clientPorts[0]
 
         $client.Refresh()
         $processSample = [pscustomobject][ordered]@{
@@ -234,7 +235,7 @@ function Invoke-Session(
             WindowTitle = $client.MainWindowTitle
         }
 
-        $checkpoints = Read-Checkpoints $timeline
+        $checkpoints = @(Read-Checkpoints $timeline)
         if ($checkpoints.Count -ne $ExpectedCheckpoints.Count) {
             $failures.Add("${Label}: expected $($ExpectedCheckpoints.Count) checkpoints, found $($checkpoints.Count)")
         }