Ship S2: the game composes and loads mod ships

Boot opens the derived catalog when GameData/Mods holds packages
(ShipModCatalog.ResolveCatalog), preloads each hull's GLB into an assembled
inactive prototype (ShipModShips), and LoadEntity clones it when the hull names
a Visual. ShipModPlan decides which anchor fills which ShipInstance slot; a
ShipModTemplate prefab carries the shared effects. Continue refuses a run that
names a design the catalog no longer holds (RunSave.RequireDesigns).

Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>

Assets/Scripts/Gameplay/ShipModVisual.cs

@@ -30,9 +30,8 @@ public static class ShipModVisual
         public Transform Get(uint index) => m_Nodes.TryGetValue(index, out var node) ? node.transform : null;
     }
 
-    public static async Task<Instance> LoadAsync(string shipPath, Transform parent)
+    public static async Task<Instance> LoadAsync(ShipModCatalog.Package package, Transform parent)
     {
-        var package = ShipModCatalog.ReadPackage(shipPath);
         var ship = package.Visual;
 
         var root = new GameObject("mod-ship:" + ship.Id);