Various cow fixes (#18602)

Reparent cow outputs to the correct grid.

Adjust produce so that cows and other multi-stomached animals can eat most produce.

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Co-authored-by: deltanedas <@deltanedas:kde.org>

Content.Server/Chemistry/ReactionEffects/CreateEntityReactionEffect.cs

@@ -1,4 +1,5 @@
 using Content.Shared.Chemistry.Reagent;
+using Robust.Shared.GameObjects;
 using Robust.Shared.Prototypes;
 using Robust.Shared.Serialization.TypeSerializers.Implementations.Custom.Prototype;
 
@@ -28,13 +29,15 @@ public sealed class CreateEntityReactionEffect : ReagentEffect
     public override void Effect(ReagentEffectArgs args)
     {
         var transform = args.EntityManager.GetComponent<TransformComponent>(args.SolutionEntity);
+        var transformSystem = args.EntityManager.System<SharedTransformSystem>();
         var quantity = Number * args.Quantity.Int();
 
         for (var i = 0; i < quantity; i++)
         {
-            args.EntityManager.SpawnEntity(Entity, transform.MapPosition);
+            var uid = args.EntityManager.SpawnEntity(Entity, transform.MapPosition);
+            transformSystem.AttachToGridOrMap(uid);
 
-            // TODO figure out how to spawn inside of containers
+            // TODO figure out how to properly spawn inside of containers
             // e.g. cheese:
             // if the user is holding a bowl milk & enzyme, should drop to floor, not attached to the user.
             // if reaction happens in a backpack, should insert cheese into backpack.