WebSG - disposal leak upon certain script errors

reproducing script:
```js
world.onenter = () => {
const scene = world.environment;

const boxNode = world.createNode({
mesh: world.createBoxMesh({
size: [1, 1, 1],
segments: [1, 1, 1],
material: world.createMaterial({
baseColorFactor: [1, 1, 1, 1],
}),
}),
collider: world.createCollider({ type: "box", size: [1, 1, 1] }),
});

boxNode.addPhysicsBody({ type: WebSG.PhysicsBodyType.Kinematic });

// cause the script to error out before the node is added to the scene
boxNode.notAFunction();

scene.addNode(boxNode);
};
```

By causing the script to error out before the node is added to the scene, a detached physics body is created that never gets disposed of, even when switching worlds.

Run the provided WebSG reproduction and observe the detached physics body after the script error and a world switch. Trace how nodes and physics bodies are owned and disposed during world changes; done means the body created before the error is disposed without requiring the node to be added to the scene.

Written by the indexing model from the issue text.