chore: initial backend + travel-proxy dockerized setup for NAS deployment

backend/Dockerfile

@@ -0,0 +1,18 @@
+FROM python:3.12-slim
+
+WORKDIR /app
+
+RUN apt-get update && apt-get install -y --no-install-recommends \
+    ca-certificates curl \
+  && rm -rf /var/lib/apt/lists/*
+
+COPY app/requirements.txt /app/requirements.txt
+RUN pip install --no-cache-dir -r /app/requirements.txt
+
+COPY app /app/app
+
+ENV PYTHONUNBUFFERED=1
+
+EXPOSE 8000
+
+CMD ["uvicorn", "app.main:app", "--host", "0.0.0.0", "--port", "8000"]