Rework wield_better_weapon considerations

[KheirFerrum]

Summary

SUMMARY: Bugfixes "Rework wield_better_weapon considerations"

Purpose of change

• Persuade NPCs to stop treating helmets as godly superweapons #1029 fixed NPCs wielding armor by making them never wield them at all. This new solution aims to allow them to do so if that's the best thing they've got, but without them literally taking off their armour to beat people to death with it.

Describe the solution

• Originally I was having trouble since anything worn is considered valid for is_armor() and is_melee only checks if a single hit deals 5 points of any type of damage. But then I remembered that weapon categories exist.

• So now, it will only compare items when worn if they have a weapon category defined, which due to how Weapon Category Update #1709 was done means basically all items that can be used as proper ranged or melee weapons.

Describe alternatives you've considered

• Keeping the old solution.
  • It's not actually a bad solution. I just feel that NPCs could be allowed to wield helmets if it's in their inventory, since currently non-armour improvised weapons are allowed for NPCs, this just removes the blanket ban and makes them more discerning.

Testing

• Give battleaxes "IS_ARMOR", "BELTED" and "OVERSIZE".
• Spawn an NPC and mind control them.
• Spawn an M4A1 and shoulder strap and install the shoulder strap into the M4A1.
• Spawn an army helmet
• Give the NPC the army helmet but do not make them wear it, check that when engaging the debug monster they will wield the helmet.
• Have the NPC wear the army helmet, check that when engaging debug monster they will not wield the helmet and leave their fleshy, crushable head exposed.
• Give the NPC the battleaxe and have them wear it. check when engaging debug monster they will wield the battleaxe.
• Give the NPC the M4A1+1 and have them wear it, check when engaging debug monster they will wield and shoot the M4A1.

Additional context

[chaosvolt]

1. Compiled and load-tested.
2. Grabbed myself an NPC companion left with only a backpack to wear to hold items for testing.
3. Put an army helmet in ther inventory, they'd use it as a weapon if it was all the had.
4. As expected, if instead asked to wear the helmet instead of leaving it in inventory, they'll choose going unarmed over exposing themselves.
5. Slapped a shoulder strap on an M4 and had them wield it, when made to engage the menacing debug monster they'll choose it over unarmed.
6. Also tested making them wear a spiked shield, they'll keep it on even if they have no weapons.

Put a zweihander inside a back scabbard loose in their inventory, they walk up to the debug monster and it then throws a read access violation:

Exception thrown: read access violation.
**who** was nullptr.

>	cataclysm-tiles.exe!character_funcs::try_wield_contents(Character & who, item & container, item * internal_item, bool penalties, int base_cost) Line 533	C++
 	cataclysm-tiles.exe!holster_actor::use(player & p, item & it, bool __formal, const tripoint & __formal) Line 2781	C++
 	cataclysm-tiles.exe!itype::invoke(player & p, item & it, const tripoint & pos, const std::string & iuse_name) Line 211	C++
 	cataclysm-tiles.exe!Character::invoke_item(item * used, const std::string & method, const tripoint & pt) Line 7235	C++
 	cataclysm-tiles.exe!npc::wield(item & it) Line 1186	C++
 	cataclysm-tiles.exe!npc::wield_better_weapon() Line 3570	C++
 	cataclysm-tiles.exe!npc::method_of_attack() Line 1372	C++
 	cataclysm-tiles.exe!npc::move() Line 785	C++
 	cataclysm-tiles.exe!game::monmove() Line 4166	C++
 	cataclysm-tiles.exe!game::do_turn() Line 1510	C++
 	cataclysm-tiles.exe!WinMain(HINSTANCE__ * __formal, HINSTANCE__ * __formal, char * __formal, int __formal) Line 739	C++
 	[External Code]	

I did this in release build after having cleaned my solution first so that's...concerning. Let me also test whether this happens in the release I've been currently playing in, to see if this is possibly an unrelated bug.

[chaosvolt]

Okay yep, tested build 2023-06-03-2309 and it just straight-up closes the game when you try that, so this is an unrelated bug. Everything else looks good.

EDIT: Tested 2023-06-08-0835 and also present, this is good to merge and then I'll resume testing a few other permutations on that bug before opening an issue.