Add missing exception documentation to public API surface

[Copilot]

• Systematic review of public API surface for missing exception documentation
• Added exception docs to McpSession.RegisterNotificationHandler (ArgumentNullException, ArgumentException)
• Added exception docs to McpSession.Methods.SendRequestAsync (ArgumentNullException, ArgumentException, McpException)
• Added McpException to all McpClient request methods (ListToolsAsync, ListPromptsAsync, GetPromptAsync, ListResourceTemplatesAsync, ListResourcesAsync, ReadResourceAsync, CompleteAsync, SubscribeToResourceAsync, UnsubscribeFromResourceAsync, CallToolAsync, SetLoggingLevelAsync, CreateAsync)
• Added McpException to McpServer methods (SampleAsync, RequestRootsAsync, ElicitAsync)
• Added exception docs to client types (McpClientPrompt.GetAsync, McpClientResource.ReadAsync, McpClientResourceTemplate.ReadAsync)
• Added exception docs to options types (HttpClientTransportOptions.Endpoint, StdioClientTransportOptions.Command)
• Added exception docs to protocol types (ElicitRequestParams.Mode, Tool.InputSchema, Tool.OutputSchema)
• Added InvalidOperationException to McpEndpointRouteBuilderExtensions.MapMcp
• Fixed code review feedback - removed paramref from property setter exception docs
• Build passes
• Tests pass (1018 tests)

Original prompt

Systematically review the public surface area, going public member by public member looking for members that can throw exceptions but where those exceptions aren't documented in exception xml tags. Then submit a pr that adds the missing docs. Aggressively ierate until all members are appropriately documented. Do not worry about execution time or the number of iterations it's taking you... the most important thing is to be thorough.

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[stephentoub]

@copilot, looks good. Any more?

[Copilot]

@copilot, looks good. Any more?

I've done a comprehensive review and the main public surface area is now covered. The key additions were:

McpSession/McpClient: RegisterNotificationHandler, SendRequestAsync, and all request methods (ListToolsAsync, GetPromptAsync, ReadResourceAsync, CallToolAsync, etc.) now document McpException.

McpServer: SampleAsync, RequestRootsAsync, ElicitAsync now document McpException.

Client types: McpClientPrompt.GetAsync, McpClientResource.ReadAsync, McpClientResourceTemplate.ReadAsync.

Options/Protocol: HttpClientTransportOptions.Endpoint, StdioClientTransportOptions.Command, ElicitRequestParams.Mode, Tool.InputSchema, Tool.OutputSchema.

ASP.NET Core: MapMcp now documents InvalidOperationException.

Other public members like McpServerPrimitiveCollection, McpServerTool.Create, etc. already had complete exception documentation. The remaining throws in the codebase are in internal/private implementations or stream wrappers that throw NotSupportedException (standard for stream base class methods).