[chore] Remove obsolete update-litegraph workflow

This workflow updated the @comfyorg/litegraph npm dependency.
No longer needed since litegraph is now a git subtree.

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

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

.github/workflows/update-litegraph.yaml

@@ -1,43 +0,0 @@
-name: Update Litegraph Dependency
-
-on:
-  workflow_dispatch:
-
-jobs:
-  update-litegraph:
-    runs-on: ubuntu-latest
-    permissions:
-      contents: write
-      pull-requests: write
-
-    steps:
-      - name: Checkout repository
-        uses: actions/checkout@v4
-
-      - name: Setup Node.js
-        uses: actions/setup-node@v4
-        with:
-          node-version: lts/*
-
-      - name: Update litegraph
-        run: npm install @comfyorg/litegraph@latest
-
-      - name: Get new version
-        id: get-version
-        run: |
-          NEW_VERSION=$(node -e "console.log(JSON.parse(require('fs').readFileSync('./package-lock.json')).packages['node_modules/@comfyorg/litegraph'].version)")
-          echo "NEW_VERSION=$NEW_VERSION" >> $GITHUB_OUTPUT
-
-      - name: Create Pull Request
-        uses: peter-evans/create-pull-request@271a8d0340265f705b14b6d32b9829c1cb33d45e
-        with:
-          token: ${{ secrets.PR_GH_TOKEN }}
-          commit-message: '[chore] Update litegraph to ${{ steps.get-version.outputs.NEW_VERSION }}'
-          title: '[chore] Update litegraph to ${{ steps.get-version.outputs.NEW_VERSION }}'
-          body: |
-            Automated update of litegraph to version ${{ steps.get-version.outputs.NEW_VERSION }}.
-            Ref: https://github.com/Comfy-Org/litegraph.js/releases/tag/v${{ steps.get-version.outputs.NEW_VERSION }}
-          branch: update-litegraph-${{ steps.get-version.outputs.NEW_VERSION }}
-          base: main
-          labels: |
-            dependencies