Alias trench_knife

BUR #58824 is pending approval.

create alias trench_knife -> combat_knife

Wikipedia stated that it's a type of combat_knife. While the usage context for World War I-era ones, some of the designs are similar to more modern ones. If you see knives with a knuckle, then I think brass knuckles should also be used.

This is analogous to the previous "shotgun vs. combat/riot/trench_shotgun" discourse on topic #27699.

Reference picture

If we do not have a tag for knuckle grips for bladed weapons, we should.

nonamethanks said in forum #437398:

If we do not have a tag for knuckle grips for bladed weapons, we should.

I'd propose the phrase knuckle_knife as the alternative since it sounds reasonable and more intuitive.