Add support for MCP protocol version 2025-03-26

[APantelides]

https://spec.modelcontextprotocol.io/specification/2025-03-26/changelog/ - There are some nice improvements to make use of. I wonder if that breaks older MCP server support or if you can support both?

[zxkane]

Notably, TS SDK v1.10.0 supports Streamable HTTP transport (introduced in version 2025-03-26).

https://github.com/modelcontextprotocol/typescript-sdk/releases/tag/1.10.0

[taylorwilsdon]

PR here @APantelides #4210