ECS and cleanup body system, merge body templates and presets into body prototypes (#11991)

Co-authored-by: Jezithyr <Jezithyr@gmail.com>

Content.Shared/Body/Systems/SharedBodySystem.cs

@@ -0,0 +1,26 @@
+using Content.Shared.Damage;
+using Content.Shared.Standing;
+using Robust.Shared.Containers;
+using Robust.Shared.Prototypes;
+
+namespace Content.Shared.Body.Systems;
+
+public abstract partial class SharedBodySystem : EntitySystem
+{
+    private const string BodyContainerId = "BodyContainer";
+
+    [Dependency] protected readonly IPrototypeManager Prototypes = default!;
+
+    [Dependency] protected readonly SharedContainerSystem Containers = default!;
+    [Dependency] protected readonly DamageableSystem Damageable = default!;
+    [Dependency] protected readonly StandingStateSystem Standing = default!;
+
+    public override void Initialize()
+    {
+        base.Initialize();
+
+        InitializeBody();
+        InitializeParts();
+        InitializeOrgans();
+    }
+}