Update ModelContextProtocolVersion to 2.0.0

[Varorbc]

Update ModelContextProtocolVersion to 2.0.0

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Update ModelContextProtocolVersion to 2.0.0

Description

Update ModelContextProtocolVersion to 2.0.0

cc @jeffhandley

[jeffhandley]

Thanks for getting this started. I have a branch ready for creating a similar PR, but we are about to release MCP 2.1.0 and I'm going to go ahead and bump directly to that version since it includes some fixes for bugs reported against 2.0.0. I have the branches ready for both main and the 10.0 release branch for servicing.

I hope you don't mind, but I'm going to close this and replace it with a fresh PR when I have that ready.