[refactor] Migrate litegraph imports from npm package to local subtree

- Updated all imports from '@comfyorg/litegraph' to '@/lib/litegraph/src/'
- Replaced deep dist imports with direct source paths
- Updated CSS import in main.ts
- All imports now use the @ alias consistently

src/main.ts

@@ -1,4 +1,4 @@
-import '@comfyorg/litegraph/style.css'
+import '@/lib/litegraph/src/style.css'
 import { definePreset } from '@primevue/themes'
 import Aura from '@primevue/themes/aura'
 import * as Sentry from '@sentry/vue'