Fix: stop reading after RunCompletedEvent to end stream

Author: rogeralsing

src/Asynkron.TestRunner/WorkerProcess.cs

@@ -147,6 +147,10 @@ public async IAsyncEnumerable<ProtocolMessage> RunAsync(
         await foreach (var msg in ReadEventsAsync(ct))
         {
             yield return msg;
+
+            // Stop after run completes
+            if (msg is RunCompletedEvent)
+                yield break;
         }
     }