Ship render: the hull collider carries the invisible material, so clones draw nothing

forceRenderingOff is not serialized, so Instantiate and SaveAsPrefabAsset dropped
it and every cloned mod ship (and every FBX-built prefab) drew its collision hull.
The collider renderer now takes the template's invisible material, as the thruster
emitter does. The preview smoke checks the collider on the clone and the prefab
smoke checks it on the configured prefab.

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

Assets/Scripts/Editor/ShipModPreview.cs

@@ -63,6 +63,9 @@ public static class ShipModPreview
         bool Inside(Component part) => part != null && part.transform.IsChildOf(ship.transform);
         Require(ship.HullColliders.Length == 1 && Inside(ship.HullColliders[0]) &&
                 ship.HullColliders[0].GetComponent<MeshCollider>() != null, "one hull collider with a MeshCollider");
+        Require(ship.HullColliders[0].GetComponentsInChildren<Renderer>(true).All(renderer =>
+                    renderer.sharedMaterials.All(material => material == ship.InvisibleMaterial)),
+                "a hull collider that draws nothing");
         Require(Inside(ship.MapIcon) && Inside(ship.Shield) && Inside(ship.TractorBeam), "map icon, shield and tractor inside the ship");
         Require(ship.ThrusterHardpoints.Select(node => node.name).SequenceEqual(plan.Thrusters) &&
                 ship.ThrusterHardpoints.All(node => Inside(node) && Inside(node.Emitter) &&