Crawling Part 1: The Knockdownening (#36881)

Co-authored-by: slarticodefast <161409025+slarticodefast@users.noreply.github.com>
Co-authored-by: metalgearsloth <comedian_vs_clown@hotmail.com>
Co-authored-by: metalgearsloth <31366439+metalgearsloth@users.noreply.github.com>
Co-authored-by: Princess Cheeseballs <66055347+Pronana@users.noreply.github.com>
Co-authored-by: ScarKy0 <scarky0@onet.eu>

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

@@ -384,11 +384,14 @@ public abstract partial class SharedGunSystem : EntitySystem
         var shotEv = new GunShotEvent(user, ev.Ammo);
         RaiseLocalEvent(gunUid, ref shotEv);
 
-        if (userImpulse && TryComp<PhysicsComponent>(user, out var userPhysics))
-        {
-            if (_gravity.IsWeightless(user, userPhysics))
-                CauseImpulse(fromCoordinates, toCoordinates.Value, user, userPhysics);
-        }
+        if (!userImpulse || !TryComp<PhysicsComponent>(user, out var userPhysics))
+            return;
+
+        var shooterEv = new ShooterImpulseEvent();
+        RaiseLocalEvent(user, ref shooterEv);
+
+        if (shooterEv.Push || _gravity.IsWeightless(user, userPhysics))
+            CauseImpulse(fromCoordinates, toCoordinates.Value, user, userPhysics);
     }
 
     public void Shoot(
@@ -629,6 +632,16 @@ public record struct AttemptShootEvent(EntityUid User, string? Message, bool Can
 [ByRefEvent]
 public record struct GunShotEvent(EntityUid User, List<(EntityUid? Uid, IShootable Shootable)> Ammo);
 
+/// <summary>
+/// Raised on an entity after firing a gun to see if any components or systems would allow this entity to be pushed
+/// by the gun they're firing. If true, GunSystem will create an impulse on our entity.
+/// </summary>
+[ByRefEvent]
+public record struct ShooterImpulseEvent()
+{
+    public bool Push;
+};
+
 public enum EffectLayers : byte
 {
     Unshaded,