feat(recipes): opt-in workflow embedding for widget recipe saves

Add a "Save Recipe with Workflow" action next to "Save Recipe" in the LoRA
widget context menu. It posts the current UI-format graph alongside the save
request so the stored preview embeds it and the recipe can send the graph back
to ComfyUI. Embedding stays opt-in rather than folded into "Save Recipe": the
workflow is by far the largest metadata field and its widget values may carry
sensitive data.

- web/comfyui: new menu entry; saveRecipeDirectly({ embedWorkflow }) posts the
  UI graph and reports the outcome (embedded / skipped) via toasts.
- save_recipe_from_widget handler: reads an optional JSON workflow field so the
  long-standing body-less POST keeps working, including from cached clients.
- RecipePersistenceService.save_recipe_from_widget: embeds the graph through
  the existing optimize_image workflow path, derives has_workflow by detection,
  and skips graphs above MAX_WORKFLOW_EMBED_BYTES with workflow_skipped.

web/comfyui/loras_widget_events.js

@@ -873,6 +873,19 @@ export function createContextMenu(x, y, loraName, widget, previewTooltip, render
     }
   );
 
+  // Save recipe with the current graph embedded. Kept opt-in rather than
+  // folded into "Save Recipe": the workflow dwarfs every other metadata field
+  // and can carry sensitive widget values, so it stays an explicit choice.
+  const saveWithWorkflowOption = createMenuItem(
+    'Save Recipe with Workflow',
+    '<svg width="14" height="14" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2"><circle cx="18" cy="5" r="3"></circle><circle cx="6" cy="12" r="3"></circle><circle cx="18" cy="19" r="3"></circle><line x1="8.59" y1="13.51" x2="15.42" y2="17.49"></line><line x1="15.41" y1="6.51" x2="8.59" y2="10.49"></line></svg>',
+    () => {
+      menu.remove();
+      document.removeEventListener('click', closeMenu);
+      saveRecipeDirectly({ embedWorkflow: true });
+    }
+  );
+
   // Move Up option with arrow up icon
   const moveUpOption = createMenuItem(
     'Move Up',
@@ -982,6 +995,7 @@ export function createContextMenu(x, y, loraName, widget, previewTooltip, render
   menu.appendChild(copyTriggerWordsOption);
   menu.appendChild(separator2);
   menu.appendChild(saveOption);
+  menu.appendChild(saveWithWorkflowOption);
   
   document.body.appendChild(menu);