Extend `--lwe-add-client-interface` to schemes other than BGV

[AlexanderViand-Intel]

The current lowering only supports RLWECiphertexts and also implicitly assumes BGV-style encode/encrypt. Somewhat related to #882 (adding encrypt/encode lowerings to poly/etc for things other than BGV)

Both probably require LWE Attr/Type fixes (see #758 and #876) before they can be realized.

[AlexanderViand-Intel]

This also reminds me that we should extend the pass that adds client helper encrypt/decrypt functions to support the rust codegen path.

Originally posted by @j2kun in https://github.com/google/heir/issues/897#issuecomment-2282367968

[github-actions[bot]]

This issue has 5 outstanding TODOs:

• lib/Pipelines/ArithmeticPipelineRegistration.cpp:135: Extend add client interface to schemes other than BGV.
• tests/Examples/openfhe/dot_product_8f_test.cpp:14: support other schemes besides BGV in add-client-interface
• tests/Examples/openfhe/dot_product_8f_test.cpp:50: support other schemes besides BGV in add-client-interface
• tests/Examples/openfhe/halevi_shoup_matmul_test.cpp:52: support other schemes besides BGV in add-client-interface
• tests/Examples/openfhe/naive_matmul_test.cpp:72: support other schemes besides BGV in add-client-interface

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