feat(43-01): add RouterNodeData type, defaults, and executor

- Add 'router' to NodeType union in types/nodes.ts
- Add RouterNodeData interface (extends BaseNodeData, no internal state)
- Add RouterNodeData to WorkflowNodeData union
- Add router dimensions (200x80) to nodeDefaults.ts and validation.ts
- Add router default data (empty object) to both files
- Add executeRouter pure passthrough function to simpleNodeExecutors.ts
- Add RouterNode export to components/nodes/index.ts

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

src/components/nodes/index.ts

@@ -17,4 +17,5 @@ export { VideoStitchNode } from "./VideoStitchNode";
 export { EaseCurveNode } from "./EaseCurveNode";
 export { VideoTrimNode } from "./VideoTrimNode";
 export { VideoFrameGrabNode } from "./VideoFrameGrabNode";
+export { RouterNode } from "./RouterNode";
 export { GroupNode } from "./GroupNode";

src/lib/quickstart/validation.ts

@@ -31,6 +31,7 @@ const VALID_NODE_TYPES: NodeType[] = [
   "easeCurve",
   "videoTrim",
   "videoFrameGrab",
+  "router",
   "glbViewer",
 ];
 
@@ -57,6 +58,7 @@ const DEFAULT_DIMENSIONS: Record<NodeType, { width: number; height: number }> =
   easeCurve: { width: 340, height: 480 },
   videoTrim: { width: 360, height: 360 },
   videoFrameGrab: { width: 320, height: 320 },
+  router: { width: 200, height: 80 },
   glbViewer: { width: 360, height: 380 },
 };
 
@@ -387,6 +389,8 @@ function createDefaultNodeData(type: NodeType): WorkflowNodeData {
         status: "idle",
         error: null,
       };
+    case "router":
+      return {};
     case "glbViewer":
       return {
         glbUrl: null,

src/store/execution/simpleNodeExecutors.ts

@@ -315,6 +315,17 @@ export async function executeImageCompare(ctx: NodeExecutionContext): Promise<vo
   });
 }
 
+/**
+ * Router node: pure passthrough with brief status flash.
+ */
+export async function executeRouter(ctx: NodeExecutionContext): Promise<void> {
+  // Router is pure passthrough — data flows via edge traversal in getConnectedInputs.
+  // Brief status flash to show execution occurred.
+  ctx.updateNodeData(ctx.node.id, { status: "loading" });
+  await new Promise(resolve => setTimeout(resolve, 50));
+  ctx.updateNodeData(ctx.node.id, { status: "complete" });
+}
+
 /**
  * GLB Viewer node: receives 3D model URL from upstream, fetches and loads it.
  */

src/store/utils/nodeDefaults.ts

@@ -18,6 +18,7 @@ import {
   EaseCurveNodeData,
   VideoTrimNodeData,
   VideoFrameGrabNodeData,
+  RouterNodeData,
   GLBViewerNodeData,
   WorkflowNodeData,
   GroupColor,
@@ -49,6 +50,7 @@ export const defaultNodeDimensions: Record<NodeType, { width: number; height: nu
   easeCurve: { width: 340, height: 480 },
   videoTrim: { width: 360, height: 360 },
   videoFrameGrab: { width: 320, height: 320 },
+  router: { width: 200, height: 80 },
   glbViewer: { width: 360, height: 380 },
 };
 
@@ -283,6 +285,8 @@ export const createDefaultNodeData = (type: NodeType): WorkflowNodeData => {
         status: "idle",
         error: null,
       } as VideoFrameGrabNodeData;
+    case "router":
+      return {} as RouterNodeData;
     case "glbViewer":
       return {
         glbUrl: null,

src/types/nodes.ts

@@ -41,6 +41,7 @@ export type NodeType =
   | "easeCurve"
   | "videoTrim"
   | "videoFrameGrab"
+  | "router"
   | "generate3d"
   | "glbViewer";
 
@@ -349,6 +350,13 @@ export interface VideoFrameGrabNodeData extends BaseNodeData {
   error: string | null;
 }
 
+/**
+ * Router node - pure passthrough routing node with dynamic multi-type handles
+ */
+export interface RouterNodeData extends BaseNodeData {
+  // No internal state - all routing is derived from edge connections
+}
+
 /**
  * Split Grid node - splits image into grid cells for parallel processing
  */
@@ -407,6 +415,7 @@ export type WorkflowNodeData =
   | EaseCurveNodeData
   | VideoTrimNodeData
   | VideoFrameGrabNodeData
+  | RouterNodeData
   | GLBViewerNodeData;
 
 /**