feat: add automated testing, validation tools, and contributor docs

[m-reuter]

• Add GitHub Actions CI workflow for automated testing
• Add validation scripts for YAML files and posts
• Add image optimization script with automatic resizing
• Add pre-commit hook for automatic validation
• Create comprehensive documentation:
  • CONTRIBUTING.md with detailed guidelines
  • QUICKSTART.md for quick reference
  • SECURITY.md with security policy
  • Content templates for posts, members, publications
• Enhance .gitignore with Jekyll, Ruby, OS, and editor files
• Add Ruby version management (.ruby-version)

[Copilot]

Pull request overview

This pull request adds comprehensive automation, validation tooling, and contributor documentation to the Deep-MI lab Jekyll website. The PR introduces GitHub Actions CI, validation scripts for data integrity, image optimization tools, and extensive documentation to streamline the contribution process.

Changes:

• Added GitHub Actions CI workflow for automated Jekyll builds and HTML validation
• Created validation scripts for YAML data files and blog post formats
• Added image optimization script with automatic resizing for member photos and publication teasers
• Created comprehensive documentation (CONTRIBUTING.md, QUICKSTART.md, SECURITY.md) and content templates
• Enhanced .gitignore with Jekyll, Ruby, OS, and editor-specific patterns
• Added .ruby-version file for Ruby version management
• Fixed minor issues in publications.yml (trailing whitespace, missing type field)

Reviewed changes

Copilot reviewed 15 out of 17 changed files in this pull request and generated 7 comments.

Show a summary per file

File	Description
.github/workflows/ci.yml	Adds CI workflow for Jekyll builds and HTML validation on pull requests
scripts/validate_yaml.rb	Validates YAML structure and required fields for members and publications
scripts/validate_posts.sh	Validates blog post filename conventions and front matter
scripts/pre-commit.sh	Pre-commit hook for running validation checks (has critical ordering issues)
scripts/optimize_images.sh	Image optimization tool using ImageMagick for member photos and publication teasers
CONTRIBUTING.md	Comprehensive contribution guidelines with validation and testing instructions
QUICKSTART.md	Quick reference guide for common tasks and troubleshooting
SECURITY.md	Security policy and best practices for the website
README.md	Updated with validation tools, scripts usage, and improved local development instructions
Gemfile	Enhanced with comments and Ruby version specification (has dependency conflict issues)
.ruby-version	Specifies Ruby 3.1.0 for consistency
.gitignore	Expanded with Jekyll, Ruby, OS, and editor patterns
_templates/*.md	Template files for posts, members, and publications
_data/publications.yml	Fixed trailing whitespace and added missing type field
favicon.ico	Added favicon binary file

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[Copilot]

Pull request overview

Copilot reviewed 15 out of 17 changed files in this pull request and generated 12 comments.

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