ci: implement Docker containerization and CI/CD pipelines

[victorbruce]

🎯 Summary

Adds Docker support and complete CI/CD automation with GitHub Actions.

✅ Features Added

Docker Setup

• Multi-stage Dockerfile (development + production)
• Docker Compose for local development
• Nginx production server configuration
• Optimized build caching and layer management

CI/CD Pipelines

• CI Pipeline: Linting, testing, and build validation on PRs
• PR Checks: PR title validation, merge conflict detection, coverage reporting
• Docker CI: Container build testing, security scanning, GHCR integration
• Deployment: Automated deployment to Render (disabled until configured)

Branch Protection

• Required PR reviews before merge
• Required status checks (lint, test, build)
• Branches must be up to date

Configuration Files

• .eslintignore - Exclude generated files from linting
• .prettierignore - Exclude generated files from formatting
• Updated npm scripts for CI compatibility

🚀 Workflows

PR → dev/main:
  ├─ Lint & Format Check
  ├─ Unit Tests
  ├─ Build Validation
  ├─ Docker Build & Test
  └─ Security Scan

Merge to main:
  └─ Deploy to Render (trigger commented out for now)

📦 Docker Commands

# Development
docker-compose up angular-dev

# Production
docker-compose up angular-prod

# Manual build
docker build --target production -t app:prod .

⚠️ Post-Merge Setup Required

1. Configure Render web service
2. Add RENDER_DEPLOY_HOOK_URL to GitHub Secrets
3. Update Render URL in deploy-render.yml
4. Uncomment deployment trigger to enable auto-deploy

✅ Testing Completed

• All workflows pass locally and in CI
• Docker builds successfully
• Containers run and serve content
• Branch protection rules active
• Linting and formatting enforced