Removed unsigned parametrization from Intervaltree
closes #30365 , #27169

Unclear if we currently consider this a feature, but I couldn't find anything explicitly asking for it so trying the removal route first

Not sure what the other alternative would be for parametrization, but I think generally we need to be careful when doing comparisons between signed and unsigned in templating or fused types

Side benefit - this gets rid of 128 build warnings and a slight perf boost to compilation
