Fix MCP samples: update MCP SDK to 0.8.0-preview.1 and fix README references (microsoft#3959)

- Update ModelContextProtocol NuGet package from 0.4.0-preview.3 to 0.8.0-preview.1
- Update System.Net.ServerSentEvents from 10.0.1 to 10.0.3
- Fix OAuth config to use DynamicClientRegistration in Agent_MCP_Server_Auth
- Fix incorrect sample name references in README files

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Author: SergeyMenshykh

dotnet/Directory.Packages.props

@@ -42,7 +42,7 @@
     <PackageVersion Include="System.Diagnostics.DiagnosticSource" Version="10.0.3" />
     <PackageVersion Include="System.Linq.AsyncEnumerable" Version="10.0.0" />
     <PackageVersion Include="System.Net.Http.Json" Version="10.0.0" />
-    <PackageVersion Include="System.Net.ServerSentEvents" Version="10.0.1" />
+    <PackageVersion Include="System.Net.ServerSentEvents" Version="10.0.3" />
     <PackageVersion Include="System.Text.Json" Version="10.0.3" />
     <PackageVersion Include="System.Threading.Channels" Version="10.0.3" />
     <PackageVersion Include="System.Threading.Tasks.Extensions" Version="4.6.3" />
@@ -102,7 +102,7 @@
     <PackageVersion Include="A2A" Version="0.3.3-preview" />
     <PackageVersion Include="A2A.AspNetCore" Version="0.3.3-preview" />
     <!-- MCP -->
-    <PackageVersion Include="ModelContextProtocol" Version="0.4.0-preview.3" />
+    <PackageVersion Include="ModelContextProtocol" Version="0.8.0-preview.1" />
     <!-- Inference SDKs -->
     <PackageVersion Include="AWSSDK.Extensions.Bedrock.MEAI" Version="4.0.5.1" />
     <PackageVersion Include="Microsoft.ML.OnnxRuntimeGenAI" Version="0.10.0" />

dotnet/samples/GettingStarted/ModelContextProtocol/Agent_MCP_Server/README.md

@@ -24,7 +24,7 @@ $env:AZURE_OPENAI_DEPLOYMENT_NAME="gpt-4o-mini"  # Optional, defaults to gpt-4o-
 
 ## Setup and Running
 
-Run the ModelContextProtocolPluginAuth sample
+Run the Agent_MCP_Server sample
 
 ```bash
 dotnet run

dotnet/samples/GettingStarted/ModelContextProtocol/Agent_MCP_Server_Auth/Program.cs

@@ -34,7 +34,10 @@
     Name = "Secure Weather Client",
     OAuth = new()
     {
-        ClientId = "ProtectedMcpClient",
+        DynamicClientRegistration = new()
+        {
+            ClientName = "ProtectedMcpClient",
+        },
         RedirectUri = new Uri("http://localhost:1179/callback"),
         AuthorizationRedirectDelegate = HandleAuthorizationUrlAsync,
     }

dotnet/samples/GettingStarted/ModelContextProtocol/Agent_MCP_Server_Auth/README.md

@@ -54,7 +54,7 @@ dotnet run
 
 The protected server will start at `http://localhost:7071`
 
-### Step 3: Run the ModelContextProtocolPluginAuth sample
+### Step 3: Run the Agent_MCP_Server_Auth sample
 
 Finally, run this client: