Context

mtest can gate tests on server version using MinServerVersion / MaxServerVersion but there is no equivalent for libmongocrypt version. Running a prose test with an unsupported libmongocrypt version creates difficult-to-diagnose errors. Unified test format defines analogous behavior with csfle.minLibmongocryptVersion.

Definition of done

Add mtest.NewOptions().MinLibmongocryptVersion() and [optionally] mtest.NewOptions().MaxLibmongocryptVersion() that skips the test when the loaded libmongocrypt version is out of range, mirroring the server-version helpers.