Replace jekyll-gh-pages.yml with unified update-content.yml workflow

[Copilot]

This PR removes the redundant jekyll-gh-pages.yml workflow file, leaving only the comprehensive update-content.yml workflow to handle all GitHub Pages deployment needs.

Problem

The repository had two GitHub Actions workflows:

• .github/workflows/jekyll-gh-pages.yml - Basic Jekyll deployment on push to main
• .github/workflows/update-content.yml - Comprehensive workflow handling content sync, Quarto rendering, Jekyll building, and GitHub Pages deployment

Having both workflows created redundancy and potential conflicts, as the update-content.yml already includes all the Jekyll build and deployment functionality found in jekyll-gh-pages.yml.

Solution

Removed the redundant jekyll-gh-pages.yml file since update-content.yml provides all the same functionality plus additional features:

• Content Synchronization: Fetches and renders content from source repositories
• Quarto Rendering: Processes .qmd files to generate HTML and PDF outputs
• Change Detection: Only commits when content actually changes
• Jekyll Building: Uses actions/jekyll-build-pages@v1 (lines 184-188)
• GitHub Pages Deployment: Complete deployment pipeline (lines 195-204)
• Scheduling: Runs daily at 6 AM UTC with manual trigger support

Verification

• ✅ YAML syntax validation passed
• ✅ Repository automation verification script confirms all functionality works
• ✅ Jekyll build and deployment steps confirmed in update-content.yml
• ✅ Proper permissions configured for both content updates and Pages deployment
• ✅ Documentation in README.md already references only update-content.yml as the unified workflow

The repository now uses a single, well-tested workflow that eliminates redundancy while maintaining all required functionality.

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