#3: Add Docker deployment support with distroless base

[octaviospain]

This PR adds production-ready Docker support for the Scryfall MCP Server with an optimized multi-stage build using Google's distroless base image.

What's Added

• Dockerfile: 3-stage build (builder → deps → runtime) with distroless base
• docker-compose.yml: Easy deployment with environment configuration
• Documentation: Simplified README section + comprehensive guide in docs/docker-deployment.md
• Configuration template: .env.docker with all available environment variables

Key Features

• Small & secure: 132MB final image, runs as non-root user (uid 65532)
• Quality gate: All 146 tests run during build - build fails if tests don't pass
• Claude Desktop/Code integration: Direct Docker execution method included

Usage

Build

docker build -t scryfall-mcp:latest .

Run with docker-compose

docker-compose up -d

Or run directly

docker run -d --name scryfall-mcp --restart unless-stopped scryfall-mcp:latest

Tested and working with both Claude Desktop and Claude Code.