Make mechanism behaviors properly update, fix eating and drinking (#2472)

* Make mechanisms properly update and fix eating and drinking

* Remove outdated component ignores

* Fix nullable error

* Fix mechanism behavior events

* Remove unnecessary code

Content.Server/GameObjects/Components/Body/Behavior/HeartBehavior.cs

@@ -0,0 +1,30 @@
+using Content.Shared.GameObjects.Components.Body.Behavior;
+using Content.Shared.GameObjects.Components.Body.Networks;
+
+namespace Content.Server.GameObjects.Components.Body.Behavior
+{
+    public class HeartBehavior : MechanismBehavior
+    {
+        private float _accumulatedFrameTime;
+
+        public override void Update(float frameTime)
+        {
+            // TODO BODY do between pre and metabolism
+            if (Parent.Body == null ||
+                !Parent.Body.Owner.HasComponent<SharedBloodstreamComponent>())
+            {
+                return;
+            }
+
+            // Update at most once per second
+            _accumulatedFrameTime += frameTime;
+
+            // TODO: Move/accept/process bloodstream reagents only when the heart is pumping
+            if (_accumulatedFrameTime >= 1)
+            {
+                // bloodstream.Update(_accumulatedFrameTime);
+                _accumulatedFrameTime -= 1;
+            }
+        }
+    }
+}