feat: add containerization support

- Add Containerfile with multi-stage build for minimal image
- Add .containerignore to exclude unnecessary files
- Add /health endpoint for container health checks
- Update main.py to expose Flask app for gunicorn

Uses Python 3.12-slim base, runs as non-root user, exposes port 8000.

.containerignore

@@ -0,0 +1,38 @@
+# Git
+.git
+.gitignore
+
+# Python
+__pycache__
+*.py[cod]
+*$py.class
+*.so
+.Python
+.venv
+.env
+*.egg-info
+dist
+build
+
+# Testing
+.pytest_cache
+.coverage
+htmlcov
+.tox
+.mypy_cache
+.ruff_cache
+
+# IDE
+.idea
+.vscode
+*.swp
+*.swo
+
+# Project specific
+data/
+*.db
+.claude
+docs/
+tests/
+*.md
+.pre-commit-config.yaml

Containerfile

@@ -0,0 +1,51 @@
+# Build stage - install dependencies
+FROM python:3.12-slim AS builder
+
+WORKDIR /app
+
+# Install uv for fast dependency management
+COPY --from=ghcr.io/astral-sh/uv:latest /uv /usr/local/bin/uv
+
+# Copy dependency files
+COPY pyproject.toml uv.lock ./
+
+# Install production dependencies only
+RUN uv sync --frozen --no-dev --no-install-project
+
+# Runtime stage - minimal image
+FROM python:3.12-slim AS runtime
+
+WORKDIR /app
+
+# Create non-root user
+RUN useradd --create-home --shell /bin/bash appuser
+
+# Copy virtual environment from builder
+COPY --from=builder /app/.venv /app/.venv
+
+# Copy application code
+COPY src/ ./src/
+COPY migrations/ ./migrations/
+COPY alembic.ini main.py ./
+
+# Set environment variables
+ENV PATH="/app/.venv/bin:$PATH"
+ENV PYTHONUNBUFFERED=1
+ENV PYTHONDONTWRITEBYTECODE=1
+ENV FLASK_ENV=production
+
+# Create data directory and set permissions
+RUN mkdir -p /app/data && chown -R appuser:appuser /app
+
+# Switch to non-root user
+USER appuser
+
+# Expose port
+EXPOSE 8000
+
+# Health check
+HEALTHCHECK --interval=30s --timeout=10s --start-period=5s --retries=3 \
+    CMD python -c "import urllib.request; urllib.request.urlopen('http://localhost:8000/health')" || exit 1
+
+# Run with gunicorn
+CMD ["gunicorn", "--bind", "0.0.0.0:8000", "--workers", "2", "--threads", "4", "main:app"]

main.py

@@ -1,6 +1,14 @@
-def main():
-    print("Hello from sneaky-klaus!")
+"""Application entry point for Sneaky Klaus.
 
+This module creates the Flask application instance for use with
+gunicorn or the Flask development server.
+"""
+
+from src.app import create_app
+
+# Create app instance for gunicorn (production)
+app = create_app()
 
 if __name__ == "__main__":
-    main()
+    # Development server
+    app.run(host="0.0.0.0", port=5000, debug=True)

src/routes/setup.py

@@ -1,6 +1,6 @@
 """Setup route for initial admin account creation."""
 
-from flask import Blueprint, abort, redirect, render_template, session, url_for
+from flask import Blueprint, abort, jsonify, redirect, render_template, session, url_for
 
 from src.app import bcrypt, db
 from src.forms import SetupForm
@@ -9,6 +9,21 @@ from src.models import Admin
 setup_bp = Blueprint("setup", __name__)
 
 
+@setup_bp.route("/health")
+def health():
+    """Health check endpoint for container orchestration.
+
+    Returns:
+        JSON response with health status.
+    """
+    try:
+        # Check database connectivity
+        db.session.execute(db.text("SELECT 1"))
+        return jsonify({"status": "healthy", "database": "connected"}), 200
+    except Exception as e:
+        return jsonify({"status": "unhealthy", "error": str(e)}), 503
+
+
 @setup_bp.route("/setup", methods=["GET", "POST"])
 def setup():
     """Handle initial admin account setup.