Fix ammo disassembly and allow for disassembly of multiple rounds

[SeventhSandwich]

SUMMARY: Bugfixes "Fix ammo disassembly and allow for disassembly of multiple rounds"

Purpose of change

Fixes #37345
The current build of the game has a two-pronged issue with disassembling ammo. Firstly, you can only disassemble in multiples of whatever the 'count' of the ammo's JSON entry is. This varies from round to round. Secondly, disassembling that amount of ammo (for instance, 50 rounds of 9mm FMJ) only returns the materials needed for one round. This is not intended behavior because the uncraft recipe for each ammo type is designed to return one round's worth of materials.

Describe the solution

This PR adds a popup window when the player chooses to disassemble ammo. It prompts the player to enter an amount of ammo to disassemble, and then starts a disassembly activity with a length of time scaled to the amount of ammo being deconstructed. After it finishes, it drops the correct number of materials.

To keep track of the number of rounds the player wants to disassemble, I store the selected quantity of rounds in the 'position' attribute of the player_activity class (which is unused during item disassembly). This is a little bit hacky, but I didn't want to add an entirely new attribute just for a single purpose like ammo disassembly. If devs would prefer that instead, I'm open to revisions.

Describe alternatives you've considered

I thought of doing something like #37494 but ruled it out because of the difficulty of upkeep. It is also nice to have the ability to disassemble fewer than 50 rounds of ammunition.

I also thought of implementing a new JSON flag to disassemble things by charge count, but I couldn't think of any use cases besides ammunition.

Testing

I built CDDA in Visual Studio 2019 and tested various types of ammo (default-kind and crafted) and tried different quantities. Everything seems to work perfectly.

Additional context

None.

[Brian-Otten]

I'm a big fan of the small extra prompt to decide how much to disassemble, so the player is fully aware of what's happening.

[ZhilkinSerg]

You need to style your changes - see #24006 for instruction for VS.

[SeventhSandwich]

I did run it through Astyle - I'm not sure why it didn't catch the spacing on that if statement

[ZhilkinSerg]

Nope, it is still not-astyled properly.