.NET Agents - Update Handoff Orchestration (#12242)

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Handoff orchestration ending task prematurely

### Description
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- Update description for _end-task_ function
- Ensure user input is published to all orchestration actors

### Contribution Checklist
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- [X] The code builds clean without any errors or warnings
- [X] The PR follows the [SK Contribution
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Author: crickman

dotnet/src/Agents/Orchestration/Handoff/HandoffActor.cs

@@ -134,6 +134,7 @@ public async ValueTask HandleAsync(HandoffMessages.Request item, MessageContext
             if (this.InteractiveCallback != null && this._taskSummary == null)
             {
                 ChatMessageContent input = await this.InteractiveCallback().ConfigureAwait(false);
+                await this.PublishMessageAsync(new HandoffMessages.Response { Message = input }, this.Context.Topic, messageId: null, messageContext.CancellationToken).ConfigureAwait(false);
                 this._cache.Add(input);
                 continue;
             }
@@ -151,7 +152,7 @@ IEnumerable<KernelFunction> CreateHandoffFunctions()
             yield return KernelFunctionFactory.CreateFromMethod(
                 this.EndAsync,
                 functionName: "end_task_with_summary",
-                description: "End the task with a summary when there is no further action to take.");
+                description: "Complete the task with a summary when no further requests are given.");
 
             foreach (KeyValuePair<string, (AgentType _, string Description)> handoff in this._handoffs)
             {