Refactor body component to use slots instead of an army of dictionaries (#3749)

* Refactor body component to use slots instead of an army of dictionaries

* Update vox

* Replace static method call with extension

* Add setpart method, replace dispose with shutdown

* Fix tests, fix not listening to slot events when setting a part

Content.IntegrationTests/Tests/GameObjects/Components/ActionBlocking/HandCuffTest.cs

@@ -78,7 +78,8 @@ namespace Content.IntegrationTests.Tests.GameObjects.Components.ActionBlocking
                 // Test to ensure a player with 4 hands will still only have 2 hands cuffed
                 AddHand(cuffed.Owner);
                 AddHand(cuffed.Owner);
-                Assert.True(cuffed.CuffedHandCount == 2 && hands.Hands.Count() == 4, "Player doesn't have correct amount of hands cuffed");
+                Assert.That(cuffed.CuffedHandCount, Is.EqualTo(2));
+                Assert.That(hands.Hands.Count(), Is.EqualTo(4));
 
                 // Test to give a player with 4 hands 2 sets of cuffs
                 cuffed.TryAddNewCuffs(human, secondCuffs);