[refactor] Improve updates/notifications domain organization (#5590)

* [refactor] Move update-related functionality to platform/updates domain

Reorganizes release management, version compatibility, and notification functionality
following Domain-Driven Design principles, mirroring VSCode's architecture pattern.

- Move releaseService.ts to platform/updates/common/
- Move releaseStore.ts to platform/updates/common/
- Move versionCompatibilityStore.ts to platform/updates/common/
- Move useFrontendVersionMismatchWarning.ts to platform/updates/common/
- Move toastStore.ts to platform/updates/common/
- Move ReleaseNotificationToast.vue to platform/updates/components/
- Move WhatsNewPopup.vue to platform/updates/components/
- Update 25+ import paths across codebase and tests

This creates a cohesive "updates" domain containing all functionality related to
software updates, version checking, release notifications, and user communication
about application state changes.

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <noreply@anthropic.com>

* fix imports

---------

Co-authored-by: Claude <noreply@anthropic.com>

src/components/helpcenter/HelpCenterMenuContent.vue

@@ -144,9 +144,9 @@ import PuzzleIcon from '@/components/icons/PuzzleIcon.vue'
 import { useConflictAcknowledgment } from '@/composables/useConflictAcknowledgment'
 import { useManagerState } from '@/composables/useManagerState'
 import { useSettingStore } from '@/platform/settings/settingStore'
-import { type ReleaseNote } from '@/services/releaseService'
+import { type ReleaseNote } from '@/platform/updates/common/releaseService'
+import { useReleaseStore } from '@/platform/updates/common/releaseStore'
 import { useCommandStore } from '@/stores/commandStore'
-import { useReleaseStore } from '@/stores/releaseStore'
 import { ManagerTab } from '@/types/comfyManagerTypes'
 import { electronAPI, isElectron } from '@/utils/envUtil'
 import { formatVersionAnchor } from '@/utils/formatUtil'