fix: restore legacy workflow.directoryPath fallback for image hydration

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

src/store/workflowStore.ts

@@ -1541,8 +1541,8 @@ const workflowStoreImpl: StateCreator<WorkflowStore> = (set, get) => ({
     const configs = loadSaveConfigs();
     const savedConfig = workflow.id ? configs[workflow.id] : null;
 
-    // Determine the workflow directory path (passed in or from saved config)
-    const directoryPath = workflowPath || savedConfig?.directoryPath || null;
+    // Determine the workflow directory path (passed in, from saved config, or embedded in legacy workflow JSON)
+    const directoryPath = workflowPath || savedConfig?.directoryPath || workflow.directoryPath || null;
 
     // Hydrate images if we have a directory path and the workflow has image refs
     let hydratedWorkflow = workflow;