[generate_manifest] update commit author & message

Author: GabrielDrapor

.github/workflows/generate-manifest.yml

@@ -57,9 +57,7 @@ jobs:
             
             Generated manifest JSON for repository: ${{ github.event.inputs.repo_url || github.event.client_payload.repo_url }}
             
-            🤖 Generated with [Claude Code](https://claude.ai/code)
-            
-            Co-Authored-By: Claude <[email protected]>
+            Co-Authored-By: Lucien
           title: "feat: Add MCP manifest for ${{ steps.repo-info.outputs.repo_name }}"
           body: |
             ## Summary