feat: initial Jimi Gallery prototype

- Public site (Home/Artists/Exhibitions/News/About/Contact) with EN/KO/JA i18n
- Admin panel with login, CRUD, image upload, multilingual editing
- Exhibition slider/lightbox view
- FastAPI + MongoDB backend, JWT auth
- Docker Compose deployment, behind nginx at jimi.yakenator.io

backend/Dockerfile

@@ -0,0 +1,24 @@
+FROM python:3.11-slim
+
+WORKDIR /app
+
+COPY backend/requirements.txt /app/requirements.txt
+RUN pip install --no-cache-dir -r /app/requirements.txt
+
+# Backend code
+COPY backend/ /app/backend/
+
+# Static frontend baked into the image so the image is self-contained in prod.
+# Local dev can still override via a volume mount if desired.
+COPY index.html artist.html artists.html exhibition.html exhibitions.html news.html about.html contact.html /static/
+COPY assets /static/assets
+COPY admin /static/admin
+
+ENV PYTHONDONTWRITEBYTECODE=1 \
+    PYTHONUNBUFFERED=1 \
+    STATIC_DIR=/static
+
+EXPOSE 8000
+
+WORKDIR /app/backend
+CMD ["uvicorn", "main:app", "--host", "0.0.0.0", "--port", "8000"]