Create Docker deployment infrastructure

This commit provides production-ready Docker deployment for the HTTP MCP wrapper.

Components:
- Dockerfile: Multi-stage build for optimized image size
  - Builder stage: Compiles dependencies and installs packages
  - Production stage: Minimal runtime image with only necessary files
  - Python 3.11 slim base image
  - Health check endpoint integration
  - Proper Python environment variables (unbuffered, no bytecode)

- docker-compose.yml: Complete orchestration setup
  - Service configuration with restart policy
  - Port mapping (8000:8000)
  - Environment variable passthrough
  - Health check configuration
  - Isolated network
  - Ready for production deployment

- .dockerignore: Optimized build context
  - Excludes Python cache, virtual environments, IDE files
  - Excludes tests and documentation
  - Reduces image size and build time

- .env.docker.example: Docker-specific environment template
  - All required Gitea configuration
  - Optional authentication settings
  - Optional tool filtering settings

Deployment:
1. Copy .env.docker.example to .env
2. Fill in Gitea credentials
3. Run: docker-compose up -d
4. Access at http://localhost:8000

This infrastructure enables easy deployment to any Docker-compatible environment (local, cloud, Kubernetes).

Closes #15

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

Dockerfile

@@ -0,0 +1,54 @@
+# Gitea HTTP MCP Wrapper Dockerfile
+# Multi-stage build for optimized image size
+
+FROM python:3.11-slim as builder
+
+# Set working directory
+WORKDIR /build
+
+# Install build dependencies
+RUN apt-get update && \
+    apt-get install -y --no-install-recommends \
+    gcc \
+    && rm -rf /var/lib/apt/lists/*
+
+# Copy requirements first for better caching
+COPY requirements.txt .
+RUN pip install --user --no-cache-dir -r requirements.txt
+
+# Copy source code
+COPY pyproject.toml .
+COPY src/ src/
+
+# Install package
+RUN pip install --user --no-cache-dir -e .
+
+# Production stage
+FROM python:3.11-slim
+
+# Set working directory
+WORKDIR /app
+
+# Copy installed packages from builder
+COPY --from=builder /root/.local /root/.local
+
+# Copy source code
+COPY src/ src/
+COPY pyproject.toml .
+
+# Make sure scripts in .local are usable
+ENV PATH=/root/.local/bin:$PATH
+
+# Set Python environment variables
+ENV PYTHONUNBUFFERED=1
+ENV PYTHONDONTWRITEBYTECODE=1
+
+# Expose default port
+EXPOSE 8000
+
+# Health check
+HEALTHCHECK --interval=30s --timeout=3s --start-period=5s --retries=3 \
+    CMD python -c "import urllib.request; urllib.request.urlopen('http://localhost:8000/health').read()"
+
+# Run the HTTP MCP server
+CMD ["gitea-http-wrapper"]