Try EvalFastRotationExt over EvalFastRotation in OpenFHE backend

We use `EvalFastRotation` in our OpenFHE backend, but there is another method `EvalFastRotationExt` https://github.com/openfheorg/openfhe-development/blob/aa391988d354d4360f390f223a90e0d1b98839d7/src/pke/include/cryptocontext.h#L2438

It says that one is supported for hybrid key switching, which we support in HEIR. However, I don't recall if we use hybrid key switching by default, or how to determine when to use it versus other options.

Search the codebase for `SetKeySwitchTechnique(HYBRID)` for references.

Main goal would be to understand the performance implications of using the `Ext` variant, and use it in HEIR when appropriate.