This addresses part of ATR-24210.
Here am unifying
The "variant" logic I originally introduced when I unified LRT (before GSF) does make sense now, so am just puting in flags to define whether we are activating HI or LRT or GSF.
Work still need to be done to unify
PrecisionElectronMenuSequences_GSF.py but I'll do that in a separated MR to make it easier to review.