Add comprehensive project documentation

[RAprogramm]

Closes #6

Changes

CHANGELOG.md

• Auto-generated from git commits using git-cliff
• Follows Keep a Changelog format
• Categorizes changes (Features, Bug Fixes, Documentation, etc.)
• Based on Conventional Commits standard
• Automatically updates on releases

cliff.toml

• Professional changelog generation configuration
• Conventional commits parsing (feat, fix, docs, chore, etc.)
• Semantic versioning support
• Keep a Changelog format compliance
• Filters out noise (dependency updates, automated commits)

CONTRIBUTING.md

• Development setup instructions
• Code style guidelines (rustfmt, clippy)
• Testing requirements (95%+ coverage)
• Pull request process and workflow
• Conventional commit format examples
• Edition 2024 and Rust 1.90+ requirements
• Licensing guidelines for contributors
• REUSE compliance instructions

SECURITY.md

• Vulnerability reporting process
• Supported versions table
• Response timeline commitments:
  • Initial response: 48 hours
  • Critical fixes: 7 days
  • High priority: 14 days
• Security best practices
• Coordinated disclosure policy
• Known limitations documentation

REUSE.toml Updates

• Added new documentation files to annotations
• Proper licensing for all new files (CC0-1.0)
• Maintains full REUSE 3.3 compliance

Benefits

• Professional open-source project appearance
• Clear contribution guidelines for developers
• Transparent security policy builds trust
• Automated changelog generation saves time
• REUSE 3.3 compliant licensing
• Required for crates.io best practices
• Better community engagement

Automated Changelog Workflow

Future releases will automatically:

1. Collect commits between versions
2. Categorize by type (feat, fix, etc.)
3. Generate formatted CHANGELOG.md
4. Include in GitHub Release notes

Testing

• All new files have REUSE compliant headers
• CHANGELOG.md generated successfully from git history
• cliff.toml configuration validated
• Documentation reviewed for accuracy

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ All tests successful. No failed tests found.

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