feat: add category support for blueprints and protect global blueprints (#8378)

## Summary

This PR adds two related features for subgraph blueprints:

### 1. Protect Global Blueprints from Deletion
- Added `isGlobalBlueprint()` helper that distinguishes blueprints by
`python_module` field
- User blueprints have `python_module: 'blueprint'`
- Global (installed) blueprints have `python_module` set to the node
pack name
- Guarded `deleteBlueprint()` to show a warning toast for global
blueprints
- Hidden delete menu in node library for global blueprints

### 2. Category Support for Blueprints
- User blueprints now use category `Subgraph Blueprints/User`
- Global blueprints use `Subgraph Blueprints/{category}` if category is
provided, otherwise `Subgraph Blueprints`
- Extended `GlobalSubgraphData.info` type with optional `category` field
- Added `category` to `zSubgraphDefinition` schema

## Files Changed
- `src/stores/subgraphStore.ts` - Core logic for both features
- `src/stores/subgraphStore.test.ts` - Tests for `isGlobalBlueprint`
- `src/components/sidebar/tabs/nodeLibrary/NodeTreeLeaf.vue` - Hide
delete menu for global blueprints
- `src/scripts/api.ts` - Extended `GlobalSubgraphData` type
- `src/platform/workflow/validation/schemas/workflowSchema.ts` - Added
category to schema
- `src/locales/en/main.json` - Added translation key

## Testing
- ✅ `pnpm typecheck` passed
- ✅ `pnpm lint` passed

┆Issue is synchronized with this [Notion
page](https://www.notion.so/PR-8378-feat-add-category-support-for-blueprints-and-protect-global-blueprints-2f66d73d36508137aa67c2d88c358b69)
by [Unito](https://www.unito.io)

---------

Co-authored-by: Subagent 5 <subagent@example.com>
Co-authored-by: Amp <amp@ampcode.com>
Co-authored-by: GitHub Action <action@github.com>
Co-authored-by: AustinMroz <austin@comfy.org>

src/components/sidebar/tabs/nodeLibrary/NodeTreeLeaf.vue

@@ -13,10 +13,7 @@
           severity="danger"
         />
       </template>
-      <template
-        v-if="nodeDef.name.startsWith(useSubgraphStore().typePrefix)"
-        #actions
-      >
+      <template v-if="isUserBlueprint" #actions>
         <Button
           variant="destructive"
           size="icon-sm"
@@ -128,8 +125,18 @@ const editBlueprint = async () => {
   await useSubgraphStore().editBlueprint(props.node.data.name)
 }
 const menu = ref<InstanceType<typeof ContextMenu> | null>(null)
+const subgraphStore = useSubgraphStore()
+const isUserBlueprint = computed(() => {
+  const name = nodeDef.value.name
+  if (!name.startsWith(subgraphStore.typePrefix)) return false
+  return !subgraphStore.isGlobalBlueprint(
+    name.slice(subgraphStore.typePrefix.length)
+  )
+})
 const menuItems = computed<MenuItem[]>(() => {
-  const items: MenuItem[] = [
+  if (!isUserBlueprint.value) return []
+
+  return [
     {
       label: t('g.delete'),
       icon: 'pi pi-trash',
@@ -137,15 +144,14 @@ const menuItems = computed<MenuItem[]>(() => {
       command: deleteBlueprint
     }
   ]
-  return items
 })
 function handleContextMenu(event: Event) {
-  if (!nodeDef.value.name.startsWith(useSubgraphStore().typePrefix)) return
+  if (!isUserBlueprint.value) return
   menu.value?.show(event)
 }
 function deleteBlueprint() {
   if (!props.node.data) return
-  void useSubgraphStore().deleteBlueprint(props.node.data.name)
+  void subgraphStore.deleteBlueprint(props.node.data.name)
 }
 
 const nodePreviewStyle = ref<CSSProperties>({