feat: add bulk actions for workflow operations in media assets (#7992)

## Summary

Add bulk action support for Add to Workflow, Open Workflow, and Export
Workflow when multiple assets are selected.

## Changes

- **What**: Bulk operations for Add to Workflow, Open/Export Workflow in
context menu

## Review Focus

- Node positioning: Multiple nodes created at same canvas center
position (may overlap)
- Context menu item ordering without separators

<img width="1927" height="921" alt="스크린샷 2026-01-13 오후 12 54 52"
src="https://github.com/user-attachments/assets/6f079232-1b24-4f02-810f-6e396916bb71"
/>


┆Issue is synchronized with this [Notion
page](https://www.notion.so/PR-7992-feat-add-bulk-actions-for-workflow-operations-in-media-assets-2e76d73d365081aa90c6fdb5039c9a3e)
by [Unito](https://www.unito.io)

src/components/sidebar/tabs/AssetsSidebarTab.vue

@@ -204,6 +204,9 @@
     @asset-deleted="refreshAssets"
     @bulk-download="handleBulkDownload"
     @bulk-delete="handleBulkDelete"
+    @bulk-add-to-workflow="handleBulkAddToWorkflow"
+    @bulk-open-workflow="handleBulkOpenWorkflow"
+    @bulk-export-workflow="handleBulkExportWorkflow"
   />
 </template>
 
@@ -321,7 +324,13 @@ const {
   deactivate: deactivateSelection
 } = useAssetSelection()
 
-const { downloadMultipleAssets, deleteMultipleAssets } = useMediaAssetActions()
+const {
+  downloadMultipleAssets,
+  deleteMultipleAssets,
+  addMultipleToWorkflow,
+  openMultipleWorkflows,
+  exportMultipleWorkflows
+} = useMediaAssetActions()
 
 // Footer responsive behavior
 const footerRef = ref<HTMLElement | null>(null)
@@ -607,6 +616,21 @@ const handleBulkDelete = async (assets: AssetItem[]) => {
   clearSelection()
 }
 
+const handleBulkAddToWorkflow = async (assets: AssetItem[]) => {
+  await addMultipleToWorkflow(assets)
+  clearSelection()
+}
+
+const handleBulkOpenWorkflow = async (assets: AssetItem[]) => {
+  await openMultipleWorkflows(assets)
+  clearSelection()
+}
+
+const handleBulkExportWorkflow = async (assets: AssetItem[]) => {
+  await exportMultipleWorkflows(assets)
+  clearSelection()
+}
+
 const handleClearQueue = async () => {
   await commandStore.execute('Comfy.ClearPendingTasks')
 }