feat: Implement Nuke-based CI/CD pipeline with versioning

[petre-c]

Summary

• Implemented comprehensive Nuke build automation system for CI/CD
• Added versioning support with VERSION file (currently v1.0.1)
• Configured GitHub Actions workflows for PR validation and release publishing

Changes Made

Build Automation

• ✅ Added Nuke build system with targets: Clean, Restore, Compile, Test, Pack, Publish
• ✅ Integrated with GitHub Actions for automated workflows
• ✅ Made tests non-blocking for package creation (integration tests require API credentials)

Version Management

• ✅ Created VERSION file for source-controlled versioning (v1.0.1)
• ✅ Added Directory.Build.props for centralized MSBuild configuration
• ✅ Implemented Git tag override for release versioning

GitHub Actions Workflows

• ✅ pr-validation.yml: Runs compilation checks on all PRs
• ✅ release.yml: Publishes NuGet packages when releases are created
• ✅ Removed old ci-cd.yml in favor of Nuke-generated workflows

Documentation

• ✅ Added BRANCH_PROTECTION.md with setup instructions
• ✅ Updated CLAUDE.md with build commands

Test Plan

• Verified Clean target removes build artifacts
• Verified Compile target builds solution successfully
• Verified Pack target creates NuGet packages
• Verified ShowVersion displays correct version (1.0.1)
• Confirmed workflows are generated correctly
• PR validation workflow will run automatically when PR is created
• Release workflow needs NUGET_API_KEY secret configured

Notes

• Tests are currently non-blocking due to integration test requirements
• To enable mandatory test passing, update Build.cs to make Pack depend on Test again
• Remember to configure branch protection rules as documented in BRANCH_PROTECTION.md

Collaboration by Claude