Duplicate field mappings do not repair signatures

[TheGlitch76]

This is hard to explain, so have a chart:
This is Lorenz 0.5.4's current output, when merging int->obf (has signatures) and obf->srg (no signatures)

Left	Right	Output
name: A->B signature: O	name: B->C signature: null	name: A->C signature: O
name: A->A signature: O	name: A->A signature: null	name: A->A signature: null

I would expect the 2nd row, which is when the mappings are "loosely duplicated", to still copy over the signature name from the left mappings.

[DenWav]

Current behavior is to assume right is most "correct" for duplicates, but I think it does make sense for that if the signature is null on the right but present on the left, to bring forward the signature from the left.

In the meantime you can fix this yourself with a custom MappingSetMergerHandler by overriding the relevant duplicate handler methods.