feat: promo items

[KiIoOnline]

Brings back limited time promotional cosmetic items for coop. Under cheats as I am not sure if it should be allowed. Linux support is needed.

[ThisAMJ]

As I said in commit comment:

complete redesign of how the command works lol
idk what/how to test this so lmk if i broke it

I do have an Unusual Prince Tavish's Crown in my TF2 inventory, is this change for the strange effects or just like force-enabling the roll cage or something?

[KiIoOnline]

This command force-enables all the pre-order weapon cosmetics like the roll cage, doesn't do anything else.
I tested the new changes on my end and it seems that it is not working as intended.
How I tested the command was as follows:

1. Load into any coop map with cheats enabled
2. Input the command with the desired changed (i.e "sar_set_promo_items_state all")
3. Restart the level and taunt to see if the changes took effect

The command goes through and no help messages are printed into the console, but no changes take effect on the player with any of the commands.

[ThisAMJ]

The command goes through and no help messages are printed into the console, but no changes take effect on the player with any of the commands.

Can you try again with the latest changes @KiIoOnline

For me (testing in splitscreen with sv_cheats 1; ss_map mp_coop_lobby_3; sar_set_promo_items_state all; restart_level) the cage on blue seems to be temporary while some kinda steam server catches up, but orange's stays on.

[KiIoOnline]

The command now properly applies and saves changes through level change, but the user can only specify for either one of the cosmetics or all of them at once. They are unable to do a combination of two cosmetics together (i.e helmet cosmetic and skins cosmetic but NOT antenna cosmetic).

Here's my method of testing:

1. Enable cheats (sv_cheats 1)
2. Input into the console map comm to load into coop (this automatically redirects you to mp_coop_community_hub, from my testing enabling splitscreen and doing ss_map has identical results to just loading directly into coop maps like this)
3. Set sar_set_promo_items_state to some other state than off
4. restart_level