Centralized management of external links (#4471)

Update the desktop guide links to make them platform and locale-aware

Edited by Terry:
Refactor external link management by introducing a centralized
useExternalLink composable with automatic locale and platform detection
for documentation URLs.

- Created useExternalLink composable - A new centralized utility for
managing all external links
- Dynamic docs URL builder (buildDocsUrl) - Automatically constructs
docs.comfy.org URLs with:
  - Locale detection (Chinese vs English)
  - Platform detection (macOS vs Windows for desktop)
  - Flexible path construction with options

┆Issue is synchronized with this [Notion
page](https://www.notion.so/PR-4471-Add-platform-and-locale-aware-desktop-guide-URL-2346d73d3650815ea4a4dd64be575bbe)
by [Unito](https://www.unito.io)

---------

Co-authored-by: Terry Jia <terryjia88@gmail.com>

src/platform/cloud/subscription/components/SubscriptionPanel.vue

@@ -309,6 +309,7 @@ import Skeleton from 'primevue/skeleton'
 import TabPanel from 'primevue/tabpanel'
 
 import CloudBadge from '@/components/topbar/CloudBadge.vue'
+import { useExternalLink } from '@/composables/useExternalLink'
 import SubscribeButton from '@/platform/cloud/subscription/components/SubscribeButton.vue'
 import SubscriptionBenefits from '@/platform/cloud/subscription/components/SubscriptionBenefits.vue'
 import { useSubscription } from '@/platform/cloud/subscription/composables/useSubscription'
@@ -316,6 +317,8 @@ import { useSubscriptionActions } from '@/platform/cloud/subscription/composable
 import { useSubscriptionCredits } from '@/platform/cloud/subscription/composables/useSubscriptionCredits'
 import { cn } from '@/utils/tailwindUtil'
 
+const { buildDocsUrl } = useExternalLink()
+
 const {
   isActiveSubscription,
   isCancelled,
@@ -340,7 +343,9 @@ const {
 
 const handleOpenPartnerNodesInfo = () => {
   window.open(
-    'https://docs.comfy.org/tutorials/api-nodes/overview#api-nodes',
+    buildDocsUrl('/tutorials/api-nodes/overview#api-nodes', {
+      includeLocale: true
+    }),
     '_blank'
   )
 }