fix: graph correctly restore html refs after exiting node group

app/src/lib/graph-interface/graph-manager.svelte.ts

@@ -486,7 +486,7 @@ export class GraphManager extends EventEmitter<{
 
   getNodeType(node: NodeInstance) {
     if (!node) {
-      console.trace('failed to get node type');
+      console.trace('failed to get node type', { node });
       return;
     }
 
@@ -685,9 +685,18 @@ export class GraphManager extends EventEmitter<{
 
   exitGroup(): { camera: [number, number, number]; nodeId: number } | false {
     if (!this.graphStack.length) return false;
-    const { savedNodes, savedEdges, outerGraph, groupId, nodeId, cameraPosition } = this.graphStack.pop()!;
+    const { savedNodes, savedEdges, outerGraph, groupId, nodeId, cameraPosition } = this.graphStack
+      .pop()!;
     const internalState = this.serialize();
 
+    // Clear stale DOM/mesh refs so the remounting components register fresh ones.
+    // The $effect guards in NodeHTML/Node only set these when undefined, so without
+    // this clear they'd keep pointing to the detached elements from before group entry.
+    for (const node of savedNodes.values()) {
+      node.state.ref = undefined;
+      node.state.mesh = undefined;
+    }
+
     // Restore live reactive nodes and edges so drag-reactivity is preserved
     this.nodes.clear();
     for (const [id, node] of savedNodes) {

app/src/lib/graph-interface/graph/Graph.svelte

@@ -97,7 +97,6 @@
 
   function getSocketType(node: NodeInstance, index: number | string): string {
     const nodeType = graph.getNodeType(node);
-    console.log({ nodeType, index });
     if (typeof index === 'string') {
       return nodeType?.inputs?.[index].type || 'unknown';
     }

app/src/lib/graph-interface/node/Node.svelte

@@ -19,7 +19,7 @@
   };
   let { node = $bindable(), inView }: Props = $props();
 
-  const nodeType = $derived(graph.getNodeType(node)!);
+  const nodeType = $derived(node ? graph.getNodeType(node) : undefined);
 
   const isActive = $derived(graphState.activeNodeId === node.id);
   const isSelected = $derived(graphState.selectedNodes.has(node.id));
@@ -33,10 +33,12 @@
   );
 
   const sectionHeights = $derived(
-    Object
+    nodeType
+      ? Object
         .keys(nodeType?.inputs || {})
         .map(key => getParameterHeight(nodeType, key) / 10)
         .filter(b => !!b)
+      : [5]
   );
 
   let meshRef: Mesh | undefined = $state();