Docker Deployment with Multi-Registry Support

This PR adds comprehensive Docker deployment infrastructure with multi-architecture builds and dual registry publishing.

Features

Multi-Architecture Support

• 🏗️ Platforms: linux/amd64, linux/arm64
• 🔄 Digest-based builds: Platform-specific images combined into multi-arch manifests

Dual Registry Publishing

• 📦 GitHub Container Registry: ghcr.io/techprimate/github-actions-utils-cli
• 🐳 Docker Hub: docker.io/techprimate/github-actions-utils-cli

Modern Metadata Management

• 🏷️ OCI-compliant labels: Using docker/metadata-action@v5
• 📝 Annotations: Attached at manifest and index levels
• 🔖 Semantic versioning: Automatic version tags (latest, v1.0.0, 1.0, 1)

Workflow Structure

• ♻️ Reusable workflows: build-cli-docker.yml for maintainability
• 🧪 PR dry-run mode: Test Docker builds in pull requests
• ⚡ Build caching: Registry-based caching for faster builds

What's Included

New Files

• .dockerignore - Optimized build context
• Dockerfile - Multi-stage build with buildpack-deps:bookworm
• .github/workflows/build-cli-docker.yml - Reusable Docker build workflow

Updated Files

• .github/workflows/release.yml - Integrated Docker build workflow
• Makefile - New Docker targets (build-linux, docker-build, docker-test, docker-run)
• README.md - Docker usage instructions and examples
• AGENTS.md - Complete Docker deployment documentation

Docker Images

Registries

# Pull from GitHub Container Registry
docker pull ghcr.io/techprimate/github-actions-utils-cli:latest

# Pull from Docker Hub
docker pull docker.io/techprimate/github-actions-utils-cli:latest

Available Tags

• latest - Latest main branch build
• v1.0.0 - Specific version releases
• 1.0 - Major.minor version
• 1 - Major version

Image Details

• Base: buildpack-deps:bookworm (~200MB)
• Platforms: linux/amd64, linux/arm64
• Entry point: /usr/local/bin/github-actions-utils-cli

Usage Examples

MCP Client Configuration

{
  "mcpServers": {
    "github-actions-utils": {
      "command": "docker",
      "args": [
        "run",
        "-i",
        "--rm",
        "ghcr.io/techprimate/github-actions-utils-cli:latest",
        "mcp"
      ]
    }
  }
}

Local Development

# Build Linux binaries
make build-linux

# Build Docker image
make docker-build

# Test Docker image
make docker-test

# Run interactively
make docker-run

Required Configuration

To enable Docker Hub publishing, add the following to repository settings:

Variables

• DOCKERHUB_USERNAME - Docker Hub username

Secrets

• DOCKERHUB_TOKEN - Docker Hub access token

Workflow Behavior

On Main Branch Push

• ✅ Builds multi-arch images
• ✅ Publishes to both registries
• ✅ Tags as latest

On Version Tag (e.g., v1.0.0)

• ✅ Builds multi-arch images
• ✅ Publishes to both registries
• ✅ Creates semantic version tags (1.0.0, 1.0, 1)

On Pull Request

• ✅ Builds images (validation only)
• ❌ Does not publish

Benefits

1. Easy Distribution - Users can pull pre-built images instead of building from source
2. Multi-Platform - Native support for both x86 and ARM architectures
3. High Availability - Images available on both GitHub and Docker Hub
4. Container Native - Perfect for containerized environments and CI/CD
5. Metadata Rich - OCI-compliant labels for better discoverability

Testing

The workflow includes comprehensive testing:

• Build validation on PRs
• Multi-platform builds
• Registry authentication
• Manifest creation and inspection

Related: Closes any Docker deployment issues (if applicable)