add mcp sample for chat.

[vwxyzh]

This pull request introduces a new project, ChatMcp, to the AzureSignalR solution and includes several changes to support this addition. The changes primarily involve adding new files for the ChatMcp project and modifying existing files to integrate the new project.

Integration of ChatMcp project:

• Project Addition:

  • Added ChatMcp project to the solution file AzureSignalR.sln and configured build settings for Debug and Release configurations. [1] [2] [3]

• Project Configuration:

  • Created ChatMcp.csproj with necessary project properties and package references.

Implementation of ChatMcp functionality:

• Core Implementation:
  • Added ChatProxy class to handle message broadcasting, implementing the IChatHub interface.
  • Added ChatTool class to provide a command-line tool for broadcasting messages using ChatProxy.
  • Added Program.cs to set up the application, configure services, and start the connection to the SignalR server.

Updates to existing ChatSample project:

• Interface Implementation:

  • Updated ChatHub class to implement the IChatHub interface and use asynchronous methods for message broadcasting and echoing.
  • Added IChatHub interface to define the contract for chat operations.

• Authentication Types:

  • Added VisualStudioCode to the AuthTypes enum and updated the ConfigureServices method to handle this new authentication type. [1] [2]

[vwxyzh]

@vicancy, why API breaking change for updating sample projects?

[vicancy]

Also add a readme to explain?