feat: add multi-stage Dockerfile for building and running app

Author: nanotaboada

Dockerfile

@@ -0,0 +1,34 @@
+# Stage 1: Build
+FROM python:3.12-slim-bookworm AS build
+
+WORKDIR /app
+
+COPY requirements.txt .
+RUN pip install --no-cache-dir -r requirements.txt
+
+COPY . .
+
+# Stage 2: Runtime
+FROM python:3.12-slim-bookworm AS runtime
+
+WORKDIR /app
+
+COPY requirements.txt .
+RUN pip install --no-cache-dir -r requirements.txt
+
+COPY models ./models
+COPY routes ./routes
+COPY schemas ./schemas
+COPY services ./services
+COPY data ./data
+COPY main.py .
+
+# Add non-root 'fastapi' user (optional for hardening)
+RUN adduser --disabled-password --gecos '' fastapi \
+    && chown -R fastapi:fastapi /app
+USER fastapi
+
+EXPOSE 9000
+ENV PYTHONUNBUFFERED=1
+
+CMD ["uvicorn", "main:app", "--host", "0.0.0.0", "--port", "9000"]