.Net Agents - Fix function result handling (#6927)

### Motivation and Context
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Empty function-result (`tool_output`) passed to assistant api.

### Description
<!-- Describe your changes, the overall approach, the underlying design.
These notes will help understanding how your code works. Thanks! -->

Change to utilize `FunctionResultContent` altered existing type
assumption. Instead of handling a `FunctionResult`, only the
`FunctionResult.Value` is now captured.

Also updated sample method naming (opportunistic)

### 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: crickman

dotnet/samples/GettingStartedWithAgents/Step1_Agent.cs

@@ -15,7 +15,7 @@ public class Step1_Agent(ITestOutputHelper output) : BaseTest(output)
     private const string ParrotInstructions = "Repeat the user message in the voice of a pirate and then end with a parrot sound.";
 
     [Fact]
-    public async Task RunAsync()
+    public async Task UseSingleChatCompletionAgentAsync()
     {
         // Define the agent
         ChatCompletionAgent agent =

dotnet/samples/GettingStartedWithAgents/Step2_Plugins.cs

@@ -17,7 +17,7 @@ public class Step2_Plugins(ITestOutputHelper output) : BaseTest(output)
     private const string HostInstructions = "Answer questions about the menu.";
 
     [Fact]
-    public async Task RunAsync()
+    public async Task UseChatCompletionWithPluginAgentAsync()
     {
         // Define the agent
         ChatCompletionAgent agent =

dotnet/samples/GettingStartedWithAgents/Step3_Chat.cs

@@ -34,7 +34,7 @@ Consider suggestions when refining an idea.
         """;
 
     [Fact]
-    public async Task RunAsync()
+    public async Task UseAgentGroupChatWithTwoAgentsAsync()
     {
         // Define the agents
         ChatCompletionAgent agentReviewer =

dotnet/samples/GettingStartedWithAgents/Step4_KernelFunctionStrategies.cs

@@ -33,7 +33,7 @@ Consider suggestions when refining an idea.
         """;
 
     [Fact]
-    public async Task RunAsync()
+    public async Task UseKernelFunctionStrategiesWithAgentGroupChatAsync()
     {
         // Define the agents
         ChatCompletionAgent agentReviewer =

dotnet/samples/GettingStartedWithAgents/Step5_JsonResult.cs

@@ -28,7 +28,7 @@ Think step-by-step and rate the user input on creativity and expressivness from
         """;
 
     [Fact]
-    public async Task RunAsync()
+    public async Task UseKernelFunctionStrategiesWithJsonResultAsync()
     {
         // Define the agents
         ChatCompletionAgent agent =

dotnet/samples/GettingStartedWithAgents/Step6_DependencyInjection.cs

@@ -30,7 +30,7 @@ Think step-by-step and rate the user input on creativity and expressivness from
         """;
 
     [Fact]
-    public async Task RunAsync()
+    public async Task UseDependencyInjectionToCreateAgentAsync()
     {
         ServiceCollection serviceContainer = new();
 

dotnet/samples/GettingStartedWithAgents/Step7_Logging.cs

@@ -37,7 +37,7 @@ Consider suggestions when refining an idea.
         """;
 
     [Fact]
-    public async Task RunAsync()
+    public async Task UseLoggerFactoryWithAgentGroupChatAsync()
     {
         // Define the agents
         ChatCompletionAgent agentReviewer =

dotnet/samples/GettingStartedWithAgents/Step8_OpenAIAssistant.cs

@@ -18,7 +18,7 @@ public class Step8_OpenAIAssistant(ITestOutputHelper output) : BaseTest(output)
     private const string HostInstructions = "Answer questions about the menu.";
 
     [Fact]
-    public async Task RunAsync()
+    public async Task UseSingleOpenAIAssistantAgentAsync()
     {
         // Define the agent
         OpenAIAssistantAgent agent =

dotnet/src/Agents/OpenAI/OpenAIAssistantChannel.cs

@@ -456,7 +456,7 @@ private static ToolOutput[] GenerateToolOutputs(FunctionResultContent[] function
         {
             FunctionResultContent functionResult = functionResults[index];
 
-            object resultValue = (functionResult.Result as FunctionResult)?.GetValue<object>() ?? string.Empty;
+            object resultValue = functionResult.Result ?? string.Empty;
 
             if (resultValue is not string textResult)
             {