Add Docker support

- Dockerfile: multi-stage Python 3.12 slim build
- docker-compose.yml: app + PostgreSQL 16 with healthcheck
- requirements.txt: fastapi, uvicorn, psycopg, passlib, jose
- .dockerignore: exclude venv, pycache, secrets
- app.py: env-based DB config (DB_HOST/PORT/NAME/USER/PASSWORD)
- README: Docker deploy instructions

Dockerfile

@@ -0,0 +1,33 @@
+# Jetour BI Dashboard — Dockerfile
+# Multi-stage: builder for slim runtime
+
+FROM python:3.12-slim AS builder
+
+WORKDIR /app
+COPY requirements.txt .
+RUN pip install --no-cache-dir --user -r requirements.txt
+
+FROM python:3.12-slim
+
+RUN apt-get update && apt-get install -y --no-install-recommends \
+    libpq5 curl \
+    && rm -rf /var/lib/apt/lists/*
+
+WORKDIR /app
+
+# Copy installed packages from builder
+COPY --from=builder /root/.local /root/.local
+
+# Copy app code
+COPY app.py .
+COPY static/ static/
+COPY migrations/ migrations/
+COPY migrate.py .
+
+# Make sure scripts in .local are in PATH
+ENV PATH=/root/.local/bin:$PATH
+
+EXPOSE 8765
+
+# Run migrations then start server
+CMD python migrate.py && uvicorn app:app --host 0.0.0.0 --port 8765