Add sync worker to detect changes and merge with fork

[Zhuul]

Add GitHub Actions workflow to sync with upstream repository.

• Create a new workflow file .github/workflows/sync_with_upstream.yml.
• Trigger the workflow on a daily schedule and on push events to the main branch.
• Add steps to fetch changes from the upstream repository.
• Add steps to merge upstream changes with the fork.
• Create a new branch if merge conflicts arise.
• Send notifications if manual intervention is required for conflict resolution.

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[github-actions]

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