Propagate tidal parameters through GWSignal

[oshaughnessy-junior]

Summary

• pass P.lambda1 and P.lambda2 into all RIFT GWSignal generation paths
• centralize construction of the GWSignal parameter dictionary
• add a public tidal-waveform regression test and a native-mode generator sanity test

This intentionally does not special-case string approximants or impose a mode ceiling; those behaviors remain with GWSignal and downstream RIFT handling.

Validation

• pytest -q MonteCarloMarginalizeCode/Code/test/waveform/test_gwsignal_tides.py
• result in the available environment: 2 passed, 1 skipped
• the optional native-mode generator test skipped because that generator is not registered in the installed environment
• public TaylorT4 tidal-vs-zero-tide generation passed