[Magiclysm] Weapon Categories touchup

[catdach]

Summary

Mods "Added the rest of the missing weapon categories for the magiclysm items, and removed the now obsolete martialarts.json file."

Purpose of change

The full completion of #55756. Some magiclysm items were still missing their weapon categories. Fixes #57111. Weapon categories also make the Magiclysm/martialarts.json file obsolete, as its only purpose was to extend the weapon lists of the vanilla martial arts.

Describe the solution

I manually dug through everything in Magiclysm/items and distributed weapon categories to the appropriate items. I wasn't super careful about it so I may have missed a few things.
Also some of the categories are a bit of a stretch, I'm pretty sure the magi staffs are supposed to be quarterstaffs but the semi-recent changes to the vanilla quarterstaffs make it hard to tell.

Deleted Magiclysm/martialarts.json.

Describe alternatives you've considered

1. Making more use of inheritance. I feel like most of the stuff in magiclysm could make better use of things like "copy_from" and "extend" as there are alot of magic items that boil down to: "vanilla item + magic effect". However that is kinda its own project and is massively out of scope for this PR.
2. Making a vanilla Falcata item for the gunblade to inherit from, instead of just giving it the medium_swords category. I really am tempted to, but I don't know enough about it to make an approximation of its dimensions and combat stats.

Testing

Started up the game and looked at some of the relevant MA weapon lists, everything looks fine.

Additional context

Magiclysm in general could use some more love. While I noticed quite a few things that need updating, for example most weapons are still using the old to-hit system. Again, alot of stuff might be solved with more liberal use of inheritance, but that's a project for another time.