Add events for GunComponent values, muzzle flashes and cartridge spread (#24077)

* Add a modifier event for GunComponent values

* Add docs

* Add VV readwrite to modified values

* Add more docs

* More docs

* Add Gun parameter to GunRefreshModifiersEvent

* Add another event for handling cartridge spread

* Fix pneumatic speed

Content.Shared/Weapons/Ranged/Systems/SharedGunSystem.Ballistic.cs

@@ -183,10 +183,10 @@ public abstract partial class SharedGunSystem
 
         // Reset shotting for cycling
         if (Resolve(uid, ref gunComp, false) &&
-            gunComp is { FireRate: > 0f } &&
+            gunComp is { FireRateModified: > 0f } &&
             !Paused(uid))
         {
-            gunComp.NextFire = Timing.CurTime + TimeSpan.FromSeconds(1 / gunComp.FireRate);
+            gunComp.NextFire = Timing.CurTime + TimeSpan.FromSeconds(1 / gunComp.FireRateModified);
         }
 
         Dirty(uid, component);