feat(quick-010): wrap workflowStore with temporal middleware and wire keyboard shortcuts

- Wrap store creation with temporal() middleware
  - partialize: Only track nodes (binary-stripped), edges, edgeStyle, groups
  - limit: 20 undo steps max
  - equality: Fast referential check using undoStateEquality()
- Add keyboard shortcuts:
  - Ctrl/Cmd+Z: Undo last change
  - Ctrl/Cmd+Shift+Z: Redo
  - Ctrl/Cmd+Y: Redo (Windows alt)
- Add drag debouncing to prevent per-pixel snapshots:
  - onNodeDragStart: Pause temporal tracking
  - onNodeDragStop: Resume tracking and capture final position
- Add _nudgeForSnapshot() helper to force snapshot capture
- Mark workflow as unsaved after undo/redo

src/components/WorkflowCanvas.tsx

@@ -281,6 +281,10 @@ export function WorkflowCanvas() {
 
 
   // Check if a node was dropped into a group and add it to that group
+  const handleNodeDragStart = useCallback(() => {
+    useWorkflowStore.temporal.getState().pause();
+  }, []);
+
   const handleNodeDragStop = useCallback(
     (_event: React.MouseEvent, node: Node) => {
       // Skip if it's a group node
@@ -313,6 +317,11 @@ export function WorkflowCanvas() {
       if (targetGroupId !== currentGroupId) {
         setNodeGroupId(node.id, targetGroupId);
       }
+
+      // Resume undo tracking after drag and capture final position
+      const temporal = useWorkflowStore.temporal.getState();
+      temporal.resume();
+      useWorkflowStore.getState()._nudgeForSnapshot();
     },
     [groups, nodes, setNodeGroupId]
   );
@@ -1081,6 +1090,39 @@ export function WorkflowCanvas() {
       return;
     }
 
+    // Handle undo (Ctrl/Cmd + Z, but NOT Ctrl/Cmd + Shift + Z)
+    if ((event.ctrlKey || event.metaKey) && (event.key === "z" || event.key === "Z") && !event.shiftKey) {
+      event.preventDefault();
+      const { undo, pastStates } = useWorkflowStore.temporal.getState();
+      if (pastStates.length > 0) {
+        undo();
+        useWorkflowStore.setState({ hasUnsavedChanges: true });
+      }
+      return;
+    }
+
+    // Handle redo (Ctrl/Cmd + Shift + Z)
+    if ((event.ctrlKey || event.metaKey) && (event.key === "z" || event.key === "Z") && event.shiftKey) {
+      event.preventDefault();
+      const { redo, futureStates } = useWorkflowStore.temporal.getState();
+      if (futureStates.length > 0) {
+        redo();
+        useWorkflowStore.setState({ hasUnsavedChanges: true });
+      }
+      return;
+    }
+
+    // Handle redo alt (Ctrl + Y — Windows convention)
+    if ((event.ctrlKey || event.metaKey) && event.key === "y") {
+      event.preventDefault();
+      const { redo, futureStates } = useWorkflowStore.temporal.getState();
+      if (futureStates.length > 0) {
+        redo();
+        useWorkflowStore.setState({ hasUnsavedChanges: true });
+      }
+      return;
+    }
+
     // Handle copy (Ctrl/Cmd + C)
     if ((event.ctrlKey || event.metaKey) && event.key === "c") {
       event.preventDefault();
@@ -1643,6 +1685,7 @@ export function WorkflowCanvas() {
         onEdgesChange={onEdgesChange}
         onConnect={handleConnect}
         onConnectEnd={handleConnectEnd}
+        onNodeDragStart={handleNodeDragStart}
         onNodeDragStop={handleNodeDragStop}
         onSelectionChange={handleSelectionChange}
         nodeTypes={nodeTypes}

src/store/workflowStore.ts

@@ -1,5 +1,6 @@
-import { create } from "zustand";
+import { create, StateCreator } from "zustand";
 import { useShallow } from "zustand/shallow";
+import { temporal, TemporalState } from "zundo";
 import {
   Connection,
   EdgeChange,
@@ -43,6 +44,7 @@ import {
   getCanvasNavigationSettings,
   saveCanvasNavigationSettings,
 } from "./utils/localStorage";
+import { partializeForUndo, undoStateEquality } from "./undoUtils";
 import {
   createDefaultNodeData,
   defaultNodeDimensions,
@@ -333,8 +335,14 @@ interface WorkflowStore {
 
   // Canvas navigation settings actions
   updateCanvasNavigationSettings: (settings: CanvasNavigationSettings) => void;
+
+  // Undo/Redo helper actions
+  _nudgeForSnapshot: () => void;
 }
 
+// Extend with TemporalState for undo/redo functionality
+export type WorkflowStoreWithTemporal = WorkflowStore & TemporalState<WorkflowStore>;
+
 let nodeIdCounter = 0;
 let groupIdCounter = 0;
 let autoSaveIntervalId: ReturnType<typeof setInterval> | null = null;
@@ -369,7 +377,8 @@ async function waitForPendingImageSyncs(timeout: number = 60000): Promise<void>
 export { generateWorkflowId, saveGenerateImageDefaults, saveNanoBananaDefaults } from "./utils/localStorage";
 export { GROUP_COLORS } from "./utils/nodeDefaults";
 
-export const useWorkflowStore = create<WorkflowStore>((set, get) => ({
+// Store implementation with temporal middleware for undo/redo
+const workflowStoreImpl: StateCreator<WorkflowStore, [["temporal", unknown]], []> = (set, get) => ({
   nodes: [],
   edges: [],
   edgeStyle: "curved" as EdgeStyle,
@@ -2111,7 +2120,23 @@ export const useWorkflowStore = create<WorkflowStore>((set, get) => ({
     set({ canvasNavigationSettings: settings });
     saveCanvasNavigationSettings(settings);
   },
-}));
+
+  // Undo/Redo helper actions
+  _nudgeForSnapshot: () => {
+    set((state) => ({ nodes: state.nodes }));
+  },
+});
+
+export const useWorkflowStore = create<WorkflowStore>()(
+  temporal(
+    workflowStoreImpl,
+    {
+      partialize: partializeForUndo as any,
+      limit: 20,
+      equality: undoStateEquality as any,
+    }
+  )
+);
 
 /**
  * Stable hook for provider API keys.