Console: survive a launcher-dropped connection during product installs

The launcher drops RPC sessions idle >30s (easily hit while the operator sits
in the install dialogs), but a dropped socket still reports Connected until an
I/O fails. InstallProductWorker then skipped its reopen, streamed the archive
on the fresh out-of-band connection, and died on the first progress poll —
and the install-completed handler registered launch entries without checking
e.Error, so AddApp's disconnected-guard exception crashed the whole console.

- PodInfo.EnsureConnectionAlive: probe an "open" connection with a Ping and
  reconnect when it is dead; used by the install and uninstall workers.
- SiteManagement.PodInfo_InstallProductCompleted: register launch entries only
  on success, and surface registration failures as the row's Install Failed
  state instead of an unhandled exception.
- Regression test pins the premise + recovery against vPOD's launcher server
  (stale socket reports open, Ping exposes it, reconnect restores service).

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

Console/TeslaConsole/SiteManagement.cs

@@ -1138,12 +1138,27 @@ public class SiteManagement : Form
 	{
 		Tuple<PodData, Guid> tuple = e.UserState as Tuple<PodData, Guid>;
 		PodData a = tuple.A;
-		foreach (LaunchData appData in BuildLaunchData(tuple.B, a))
+		Exception error = e.Error;
+		// Register the launch entries only when the transfer succeeded, and never
+		// let a pod that dropped mid-install take the console down (AddApp throws
+		// when the connection is gone).
+		if (error == null)
 		{
-			a.Conn.AddApp(appData);
+			try
+			{
+				foreach (LaunchData appData in BuildLaunchData(tuple.B, a))
+				{
+					a.Conn.AddApp(appData);
+				}
+			}
+			catch (Exception ex)
+			{
+				Program.LogException(ex, "Registering launch entries failed.");
+				error = ex;
+			}
 		}
 		a.OperationInProgress = false;
-		a.Error = e.Error;
+		a.Error = error;
 		dgvPods.InvalidateCell(colOperationProgress.Index, mPods.IndexOf(a));
 	}