refactor: remove redundant autonomous turn counter reset from ContinueTurnAsync

dotnet/src/Microsoft.Agents.AI.Workflows/Specialized/HandoffAgentExecutor.cs

@@ -342,12 +342,6 @@ internal sealed class HandoffAgentExecutor :
                     skipAddIncoming: true).ConfigureAwait(false);
             }
 
-            // Reset the counter when ending the turn (handoff requested or turn limit reached).
-            // This also covers the case where the turn is interrupted by outstanding requests:
-            // the counter is reset at the start of the next HandleAsync call, but we still
-            // clean up here on a normal turn exit for clarity.
-            this._autonomousModeTurnCount = 0;
-
             HandoffState outgoingState = new(state.IncomingState.TurnToken, result.HandoffTargetId, this._agent.Id);
 
             await context.SendMessageAsync(outgoingState, cancellationToken).ConfigureAwait(false);

dotnet/tests/Microsoft.Agents.AI.Workflows.UnitTests/HandoffAgentExecutorTests.cs

@@ -242,7 +242,11 @@ public class HandoffAgentExecutorTests : AIAgentHostingExecutorTestsBase
     public async Task Test_HandoffAgentExecutor_AutonomousMode_InvokesAgentUpToTurnLimitPlusOne(int turnLimit)
     {
         // Arrange: agent with many prepared turns; no handoff ever requested; autonomous mode ON
-        int totalTurns = turnLimit + 2; // More turns prepared than the limit to detect over-invocation
+        // We prepare (turnLimit + 2) turns so that if the implementation over-invokes by one,
+        // TestReplayAgent.Turn will be (turnLimit + 2) rather than the expected (turnLimit + 1).
+        // TestReplayAgent does NOT increment Turn when it runs out of prepared messages, so preparing
+        // exactly (turnLimit + 1) would make an extra invocation silently undetectable.
+        int totalTurns = turnLimit + 2;
         TestReplayAgent agent = new(
             Enumerable.Range(0, totalTurns)
                       .Select(i => TestReplayAgent.ToChatMessages($"Turn {i} response"))