Convert StomachBehavior to a component/system + rejig body namespaces (#5249)

* Convert StomachBehavior to a component/system + rejig body namespaces

* test

* slightly more namespace changes

* remove

* Hello?????

* fuck you github test runner

* reviews

* oobsy!

Content.Server/Chemistry/EntitySystems/SolutionContainerSystem.cs

@@ -215,7 +215,7 @@ namespace Content.Server.Chemistry.EntitySystems
             [NotNullWhen(true)] out Solution? solution,
             SolutionContainerManagerComponent? solutionsMgr = null)
         {
-            if (!Resolve(uid, ref solutionsMgr))
+            if (!Resolve(uid, ref solutionsMgr, false))
             {
                 solution = null;
                 return false;