* Add more tests
* Fix some code smells
* Remove more code smells
* Combine "ServerIntegrationTests" and "ClientIntegrationTests" because both are client integration tests just using different servers
* Clean up resources after test
* Improve kill logic for spawned child processes
* Improved testability for Stdio
* Fix SseIntegration tests
We try hard to avoid creating unnecessary JsonSerializerOptions, as each can have a non-trivial overhead due to how reflection is used by JsonSerializer and the JSO instance serving as a cache. Rather than creating a new JSO for each transport / endpoint, this can just use a singleton. The only thing it loses is logging when the converter fails, but all of those paths are also throwing an exception, which can be logged higher in the call stack.
* Server support (stdio)
* TestServer project
* Refactored McpClient class to extract shared endpoint logic (with McpServer) to a base class, McpJsonRpcEndpoint.
* Improved xmldoc comments for protocol types, mirroring specification schema comments.
* Update README.MD
