tldr; The Extensions API version should just be MAJOR.MINOR, but the SDK should retain MAJOR.MINOR.PATCH version.

As discussed in Extensions Eng Weekly, the "patch" for the API doesn't mean anything since the API describe an interface, not an implementation that could have patch fixes. Change to the API will classify as major or minor version bumps.

On the host-side, each API version will be tied to a MongoDB version (X.Y.Z). On the extension-side, the SDK should maintain a patch version since it's possible we would have patch changes to the SDK on the same MAJOR.MINOR API version.