Add Docker setup with AI ensemble integration and execution loop

Dockerize the order executor with python:3.11-slim, add docker-compose
with config volume mount for hot-reload of system.yaml settings. Integrate
AI ensemble validation into order execution pipeline and add configurable
interval loop (default 60s) to replace container restart cycling.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Dockerfile

@@ -0,0 +1,19 @@
+FROM python:3.11-slim
+
+# LightGBM needs libgomp
+RUN apt-get update && apt-get install -y --no-install-recommends \
+    libgomp1 && rm -rf /var/lib/apt/lists/*
+
+WORKDIR /app
+
+COPY requirements.docker.txt .
+RUN pip install --no-cache-dir -r requirements.docker.txt
+
+COPY config/system.yaml config/system.yaml
+COPY src/ src/
+COPY sql/ sql/
+
+RUN mkdir -p logs models
+
+ENV PYTHONUNBUFFERED=1
+CMD ["python", "src/order_executor.py"]