Add Metadata delegation to DelegatingMcpServerTool, DelegatingMcpServerPrompt, and DelegatingMcpServerResource

Co-authored-by: stephentoub <2642209+stephentoub@users.noreply.github.com>

Author: Copilot

src/ModelContextProtocol.Core/Server/DelegatingMcpServerPrompt.cs

@@ -23,6 +23,9 @@ protected DelegatingMcpServerPrompt(McpServerPrompt innerPrompt)
     /// <inheritdoc />
     public override Prompt ProtocolPrompt => _innerPrompt.ProtocolPrompt;
 
+    /// <inheritdoc />
+    public override IReadOnlyList<object> Metadata => _innerPrompt.Metadata;
+
     /// <inheritdoc />
     public override ValueTask<GetPromptResult> GetAsync(
         RequestContext<GetPromptRequestParams> request, 

src/ModelContextProtocol.Core/Server/DelegatingMcpServerResource.cs

@@ -26,6 +26,9 @@ protected DelegatingMcpServerResource(McpServerResource innerResource)
     /// <inheritdoc />
     public override ResourceTemplate ProtocolResourceTemplate => _innerResource.ProtocolResourceTemplate;
 
+    /// <inheritdoc />
+    public override IReadOnlyList<object> Metadata => _innerResource.Metadata;
+
     /// <inheritdoc />
     public override bool IsMatch(string uri) => _innerResource.IsMatch(uri);
 

src/ModelContextProtocol.Core/Server/DelegatingMcpServerTool.cs

@@ -23,6 +23,9 @@ protected DelegatingMcpServerTool(McpServerTool innerTool)
     /// <inheritdoc />
     public override Tool ProtocolTool => _innerTool.ProtocolTool;
 
+    /// <inheritdoc />
+    public override IReadOnlyList<object> Metadata => _innerTool.Metadata;
+
     /// <inheritdoc />
     public override ValueTask<CallToolResult> InvokeAsync(
         RequestContext<CallToolRequestParams> request,