[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/composables/node/useNodePricing.ts

@@ -1,5 +1,5 @@
-import type { LGraphNode } from '@comfyorg/litegraph'
-import type { IComboWidget } from '@comfyorg/litegraph/dist/types/widgets'
+import type { LGraphNode } from '@/lib/litegraph/src/litegraph'
+import type { IComboWidget } from '@/lib/litegraph/src/types/widgets'
 
 /**
  * Function that calculates dynamic pricing based on node widget values