Remove IActionBlocker.CanMove (#4449)

* Remove IActionBlocker.CanMove

Ported the remainders over to using MovementAttemptEvent which should also help make mob movement a bit faster.

* Make that check faster

Content.Shared/MobState/EntitySystems/SharedMobStateSystem.cs

@@ -1,4 +1,6 @@
 using Content.Shared.MobState.Components;
+using Content.Shared.MobState.State;
+using Content.Shared.Movement;
 using Content.Shared.Pulling.Events;
 using Robust.Shared.GameObjects;
 
@@ -11,6 +13,7 @@ namespace Content.Shared.MobState.EntitySystems
             base.Initialize();
 
             SubscribeLocalEvent<SharedMobStateComponent, StartPullAttemptEvent>(OnStartPullAttempt);
+            SubscribeLocalEvent<SharedMobStateComponent, MovementAttemptEvent>(OnMoveAttempt);
         }
 
         private void OnStartPullAttempt(EntityUid uid, SharedMobStateComponent component, StartPullAttemptEvent args)
@@ -18,5 +21,18 @@ namespace Content.Shared.MobState.EntitySystems
             if(component.IsIncapacitated())
                 args.Cancel();
         }
+
+        private void OnMoveAttempt(EntityUid uid, SharedMobStateComponent component, MovementAttemptEvent args)
+        {
+            switch (component.CurrentState)
+            {
+                case SharedCriticalMobState:
+                case SharedDeadMobState:
+                    args.Cancel();
+                    return;
+                default:
+                    return;
+            }
+        }
     }
 }