[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/scripts/domWidget.ts

@@ -1,12 +1,16 @@
-import { LGraphNode, LegacyWidget, LiteGraph } from '@comfyorg/litegraph'
-import type {
-  IBaseWidget,
-  IWidgetOptions
-} from '@comfyorg/litegraph/dist/types/widgets'
 import _ from 'lodash'
 import { type Component, toRaw } from 'vue'
 
 import { useChainCallback } from '@/composables/functional/useChainCallback'
+import {
+  LGraphNode,
+  LegacyWidget,
+  LiteGraph
+} from '@/lib/litegraph/src/litegraph'
+import type {
+  IBaseWidget,
+  IWidgetOptions
+} from '@/lib/litegraph/src/types/widgets'
 import type { InputSpec } from '@/schemas/nodeDef/nodeDefSchemaV2'
 import { useDomWidgetStore } from '@/stores/domWidgetStore'
 import { generateUUID } from '@/utils/formatUtil'