feat: add Update ComfyUI option to Help Center for non-desktop environments (#7578)

## Summary

- Adds "Update ComfyUI" menu item to Help Center for portable/localhost
environments
- Wires existing `/v2/manager/queue/update_comfyui` endpoint to the
frontend
- Only visible in non-desktop, non-cloud distributions (where Electron
update mechanism isn't available)

## Changes

1. **Service layer**: Added `updateComfyUI()` method to
`comfyManagerService.ts`
2. **UI**: Added menu item with download icon to
`HelpCenterMenuContent.vue`
3. **i18n**: Added translation key for the new menu item

## Context

The new Manager UI (v4) lost the ability to update ComfyUI core in
non-desktop environments. This restores that functionality by
integrating the existing manager endpoint into the Help Center menu.

## Test plan

- [ ] Verify menu item appears in portable/localhost environments
- [ ] Verify menu item does NOT appear in desktop (Electron)
environments
- [ ] Verify menu item does NOT appear in cloud environments
- [ ] Test clicking the menu item triggers update and reboot

┆Issue is synchronized with this [Notion
page](https://www.notion.so/PR-7578-feat-add-Update-ComfyUI-option-to-Help-Center-for-non-desktop-environments-2cc6d73d3650811e9e4fe55515f50333)
by [Unito](https://www.unito.io)

src/workbench/extensions/manager/services/comfyManagerService.ts

@@ -12,6 +12,7 @@ type ManagerQueueStatus = components['schemas']['QueueStatus']
 type InstallPackParams = components['schemas']['InstallPackParams']
 type InstalledPacksResponse = components['schemas']['InstalledPacksResponse']
 type UpdateAllPacksParams = components['schemas']['UpdateAllPacksParams']
+type UpdateComfyUIParams = components['schemas']['UpdateComfyUIParams']
 type ManagerTaskHistory = components['schemas']['HistoryResponse']
 type QueueTaskItem = components['schemas']['QueueTaskItem']
 
@@ -26,6 +27,7 @@ enum ManagerRoute {
   RESET_QUEUE = 'manager/queue/reset',
   QUEUE_STATUS = 'manager/queue/status',
   UPDATE_ALL = 'manager/queue/update_all',
+  UPDATE_COMFYUI = 'manager/queue/update_comfyui',
   LIST_INSTALLED = 'customnode/installed',
   GET_NODES = 'customnode/getmappings',
   IMPORT_FAIL_INFO = 'customnode/import_fail_info',
@@ -271,6 +273,33 @@ export const useComfyManagerService = () => {
     )
   }
 
+  const updateComfyUI = async (
+    params: UpdateComfyUIParams = { is_stable: true },
+    ui_id?: string,
+    signal?: AbortSignal
+  ) => {
+    const errorContext = 'Updating ComfyUI'
+    const routeSpecificErrors = {
+      400: 'Bad Request: Missing required parameters',
+      403: 'Forbidden: To use this action, a security_level of `middle or below` is required'
+    }
+
+    const queryParams = {
+      client_id: api.clientId ?? api.initialClientId ?? 'unknown',
+      ui_id: ui_id || uuidv4(),
+      ...params
+    }
+
+    return executeRequest<null>(
+      () =>
+        managerApiClient.get(ManagerRoute.UPDATE_COMFYUI, {
+          params: queryParams,
+          signal
+        }),
+      { errorContext, routeSpecificErrors, isQueueOperation: true }
+    )
+  }
+
   const rebootComfyUI = async (signal?: AbortSignal) => {
     const errorContext = 'Rebooting ComfyUI'
     const routeSpecificErrors = {
@@ -335,6 +364,7 @@ export const useComfyManagerService = () => {
     updateAllPacks,
 
     // System operations
+    updateComfyUI,
     rebootComfyUI,
     isLegacyManagerUI
   }