Shadow anomaly returns (#24629)

* content

* add cat

* ambient

* I FORGOT HEARTS!

* fix ambient

* some fixes

* canCollide: false

* connect to damageable

* pi

* remove fx

* some fixes

* *sad bruh*

* hazed

* Update base_shadow.yml

Content.Shared/Flash/FlashableComponent.cs

@@ -1,3 +1,4 @@
+using Content.Shared.Physics;
 using Robust.Shared.GameStates;
 using Robust.Shared.Serialization;
 
@@ -9,6 +10,9 @@ namespace Content.Shared.Flash
         public float Duration;
         public TimeSpan LastFlash;
 
+        [DataField]
+        public CollisionGroup CollisionGroup = CollisionGroup.Opaque;
+
         public override bool SendOnlyToOwner => true;
     }