ci: add manual dependency update workflow

[daggerok]

Summary

• remove automatic dependency update checks from the main CI workflow
• add a manual Dependency Updates workflow with workflow_dispatch
• commit dependency updates using Maksim Kostromin <daggerok@gmail.com>
• push updates with a PAT-based secret so the resulting push can trigger GitHub Pages deploy workflows

Important setup

Create a repository secret named WORKFLOW_PUSH_TOKEN.

Recommended token options:

• classic PAT: repo + workflow
• or a fine-grained PAT with contents write access to this repository

Why: pushes performed with the default GITHUB_TOKEN do not trigger other push-based workflows, but a PAT push will.

Manual usage

1. Open Actions → Dependency Updates
2. Click Run workflow
3. Keep target_branch=master (or choose another branch)
4. If dependency updates exist, the workflow will:
   • update package.json and bun.lock
   • validate build and build-github-pages
   • commit with your requested Git identity
   • push to the selected branch

Validation

• YAML syntax validated for updated workflow files
• workflow logic reviewed against current GitHub Pages push-triggered setup