.Net: Processes fixing sample 1 to emit exit event (#9294)

### Description
Fixing processes sample 01 to emit exit event conditionally

### Contribution Checklist

<!-- Before submitting this PR, please make sure: -->

- [x] The code builds clean without any errors or warnings
- [x] The PR follows the [SK Contribution
Guidelines](https://github.com/microsoft/semantic-kernel/blob/main/CONTRIBUTING.md)
and the [pre-submission formatting
script](https://github.com/microsoft/semantic-kernel/blob/main/CONTRIBUTING.md#development-scripts)
raises no violations
- [x] All unit tests pass, and I have added new tests where possible
- [x] I didn't break anyone 😄

Author: esttenorio

dotnet/samples/GettingStartedWithProcesses/Events/CommonEvents.cs

@@ -8,4 +8,5 @@ public static class CommonEvents
 {
     public static readonly string UserInputReceived = nameof(UserInputReceived);
     public static readonly string AssistantResponseGenerated = nameof(AssistantResponseGenerated);
+    public static readonly string Exit = nameof(Exit);
 }

dotnet/samples/GettingStartedWithProcesses/SharedSteps/ScriptedUserInputStep.cs

@@ -48,23 +48,42 @@ public override ValueTask ActivateAsync(KernelProcessStepState<UserInputState> s
         return ValueTask.CompletedTask;
     }
 
+    internal string GetNextUserMessage()
+    {
+        if (_state != null && _state.CurrentInputIndex >= 0 && _state.CurrentInputIndex < this._state.UserInputs.Count)
+        {
+            var userMessage = this._state!.UserInputs[_state.CurrentInputIndex];
+            _state.CurrentInputIndex++;
+
+            Console.ForegroundColor = ConsoleColor.Yellow;
+            Console.WriteLine($"USER: {userMessage}");
+            Console.ResetColor();
+
+            return userMessage;
+        }
+
+        Console.WriteLine("SCRIPTED_USER_INPUT: No more scripted user messages defined, returning empty string as user message");
+        return string.Empty;
+    }
+
     /// <summary>
     /// Gets the user input.
+    /// Could be overridden to customize the output events to be emitted
     /// </summary>
     /// <param name="context">An instance of <see cref="KernelProcessStepContext"/> which can be
     /// used to emit events from within a KernelFunction.</param>
     /// <returns>A <see cref="ValueTask"/></returns>
     [KernelFunction(Functions.GetUserInput)]
-    public async ValueTask GetUserInputAsync(KernelProcessStepContext context)
+    public virtual async ValueTask GetUserInputAsync(KernelProcessStepContext context)
     {
-        var userMessage = _state!.UserInputs[_state.CurrentInputIndex];
-        _state.CurrentInputIndex++;
-
-        Console.ForegroundColor = ConsoleColor.Yellow;
-        Console.WriteLine($"USER: {userMessage}");
-        Console.ResetColor();
-
+        var userMessage = this.GetNextUserMessage();
         // Emit the user input
+        if (string.IsNullOrEmpty(userMessage))
+        {
+            await context.EmitEventAsync(new() { Id = CommonEvents.Exit });
+            return;
+        }
+
         await context.EmitEventAsync(new() { Id = CommonEvents.UserInputReceived, Data = userMessage });
     }
 }

dotnet/samples/GettingStartedWithProcesses/Step01/Step01_Processes.cs

@@ -95,6 +95,22 @@ public override void PopulateUserInputs(UserInputState state)
             state.UserInputs.Add("How low is the lowest valley?");
             state.UserInputs.Add("How wide is the widest river?");
             state.UserInputs.Add("exit");
+            state.UserInputs.Add("This text will be ignored because exit process condition was already met at this point.");
+        }
+
+        public override async ValueTask GetUserInputAsync(KernelProcessStepContext context)
+        {
+            var userMessage = this.GetNextUserMessage();
+
+            if (string.Equals(userMessage, "exit", StringComparison.OrdinalIgnoreCase))
+            {
+                // exit condition met, emitting exit event
+                await context.EmitEventAsync(new() { Id = ChatBotEvents.Exit, Data = userMessage });
+                return;
+            }
+
+            // emitting userInputReceived event
+            await context.EmitEventAsync(new() { Id = CommonEvents.UserInputReceived, Data = userMessage });
         }
     }
 

dotnet/samples/GettingStartedWithProcesses/Step02/Step02_AccountOpening.cs

@@ -47,6 +47,10 @@ private KernelProcess SetupAccountOpeningProcess<TUserInputStep>() where TUserIn
             .OnEvent(CommonEvents.UserInputReceived)
             .SendEventTo(new ProcessFunctionTargetBuilder(newCustomerFormStep, CompleteNewCustomerFormStep.Functions.NewAccountProcessUserInfo, "userMessage"));
 
+        userInputStep
+            .OnEvent(CommonEvents.Exit)
+            .StopProcess();
+
         // When the newCustomerForm step emits needs more details, send message to displayAssistantMessage step
         newCustomerFormStep
             .OnEvent(AccountOpeningEvents.NewCustomerFormNeedsMoreDetails)