Add combined Dockerfile for single-container deployment

Dockerfile

@@ -0,0 +1,41 @@
+# Combined Dockerfile for FastAPI backend + React frontend
+# Stage 1: Build frontend
+FROM node:18-alpine AS frontend-builder
+WORKDIR /app/frontend
+COPY frontend/package*.json ./
+RUN npm ci
+COPY frontend/ ./
+RUN npm run build
+
+# Stage 2: Build backend and serve both
+FROM python:3.11-slim
+WORKDIR /app
+
+# Install system dependencies
+RUN apt-get update && apt-get install -y --no-install-recommends \
+    curl \
+    && rm -rf /var/lib/apt/lists/*
+
+# Copy backend requirements and install
+COPY backend/requirements.txt ./backend/
+RUN pip install --no-cache-dir -r backend/requirements.txt
+
+# Copy backend code
+COPY backend/ ./backend/
+
+# Copy built frontend from builder stage
+COPY --from=frontend-builder /app/frontend/dist ./frontend/dist
+
+# Set environment variables
+ENV PYTHONUNBUFFERED=1
+ENV PYTHONDONTWRITEBYTECODE=1
+
+# Expose port
+EXPOSE 8000
+
+# Health check
+HEALTHCHECK --interval=30s --timeout=10s --start-period=5s --retries=3 \
+    CMD curl -f http://localhost:8000/health || exit 1
+
+# Run FastAPI server with static file serving
+CMD ["python", "-m", "uvicorn", "app.main:app", "--host", "0.0.0.0", "--port", "8000"]