Twitch can no longer lower your next move beneath 1, no more obscene …

…embeds on reagent spears (Bubberstation#2536)

## About The Pull Request
This fixes two bugs. Quoting the player reported bug:

Exploit #1 - Twitch Next Move modificier

This one needs a bit of VV to test mostly to speed up the conditions,
but its doable by a miner with a bit of skill.

You need the berserker armor of the chosen one, or alternatively, the
Dexterous mutation and a way to remove it (I think you can do so with
mutadone, but never tried, regardless!) and Twitch.
The short of it is that the next move variable is always edited with
multiplicatives, but Twitch was coded with an aditive, so alternating
one and another and then removing one effect and letting the other run
out would net you with a lower than 1 next move variable.

Exploit #2  - God Slaying Spear

This one is easy to test, basically you all got a spear with better
embeed stats than ninja stars, which embeeds most of the time thanks to
its high embeed chance, plus its armor penetration, with no chance for
it to fall out naturally so it has to be manually removed. Since it has
a Bulky weight class, its damage multiplier is 4 plus the pain
multiplier being 6, doing 24 damage per tick and on extraction, being
able to kill a person that gets it in 10 seconds, even if armored.

We had a whole clique abusing this as icecats on nova, and even
combining it with morphine.


https://github.com/Bubberstation/Bubberstation/blob/master/modular_skyrat/modules/reagent_forging/code/forge_weapons.dm#L136

## Why It's Good For The Game
Fixes some seriously game breaking bugs no one's abused yet, discovered
on Nova,

## Proof Of Testing

<details>
<summary>Screenshots/Videos</summary>

</details>

## Changelog

:cl: OrbisAnima (code for 1), ReturnToZender (code for 2)
fix: Fixes an exploit with Twitch, and the reagent forged spear's
embedding.
/:cl:

---------

Co-authored-by: Arturlang <[email protected]>

modular_skyrat/modules/deforest_medical_items/code/chemicals/twitch.dm

@@ -43,7 +43,7 @@
 	. = ..()
 
 	our_guy.add_movespeed_modifier(/datum/movespeed_modifier/reagent/twitch)
-	our_guy.next_move_modifier -= 0.3 // For the duration of this you move and attack faster
+	our_guy.next_move_modifier *= 0.7 // For the duration of this you move and attack faster
 
 	our_guy.sound_environment_override = SOUND_ENVIRONMENT_DIZZY
 
@@ -72,7 +72,7 @@
 	. = ..()
 
 	our_guy.remove_movespeed_modifier(/datum/movespeed_modifier/reagent/twitch)
-	our_guy.next_move_modifier += (overdosed ? 0.5 : 0.3)
+	our_guy.next_move_modifier /= (overdosed ? 0.49 : 0.7)
 
 	our_guy.sound_environment_override = NONE
 
@@ -146,7 +146,7 @@
 
 	RegisterSignal(our_guy, COMSIG_ATOM_PRE_BULLET_ACT, PROC_REF(dodge_bullets))
 
-	our_guy.next_move_modifier -= 0.2 // Overdosing makes you a liiitle faster but you know has some really bad consequences
+	our_guy.next_move_modifier *= 0.7 // Overdosing makes you a liiitle faster but you know has some really bad consequences
 
 	if(!our_guy.hud_used)
 		return

modular_skyrat/modules/reagent_forging/code/forge_weapons.dm

@@ -122,7 +122,7 @@
 	inhand_icon_state = "spear"
 	worn_icon_state = "spear_back"
 	throwforce = 15 //not a javelin, throwing specialty is for the axe.
-	embed_data = /datum/embed_data/forged_spear
+	embed_data = /datum/embed_data/spear
 	slot_flags = ITEM_SLOT_BACK
 	w_class = WEIGHT_CLASS_BULKY
 	resistance_flags = FIRE_PROOF
@@ -133,11 +133,6 @@
 	bare_wound_bonus = 15
 	sharpness = SHARP_POINTY
 
-/datum/embed_data/forged_spear
-	embed_chance = 75
-	fall_chance = 0
-	pain_mult = 6
-
 /obj/item/forging/reagent_weapon/spear/Initialize(mapload)
 	. = ..()
 	AddComponent(/datum/component/jousting, max_tile_charge = 9, min_tile_charge = 6)