M1: Grundgerüst, Datenmodell und Admin

Django-5.2-Projekt mit uv, django-environ und Docker-Compose-Setup
(web + Postgres, WeasyPrint-Systembibliotheken im Image). Vollständiges
Datenmodell (Firma, Therapeut, Auftraggeber, Teilnehmer, Leistungsart,
Leistung, InvoiceLog, InvoiceCounter) mit Admin, Login-Flow und
Platzhalter-Dashboard. Fortschritt in FORTSCHRITT.md.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_016yy3uodsai6Ytt3GJ7tBdz

Dockerfile

@@ -0,0 +1,48 @@
+# syntax=docker/dockerfile:1
+
+# --- Builder: resolve & install dependencies with uv into a venv ---------------
+FROM python:3.13-slim AS builder
+
+COPY --from=ghcr.io/astral-sh/uv:0.8 /uv /uvx /bin/
+
+ENV UV_COMPILE_BYTECODE=1 \
+    UV_LINK_MODE=copy \
+    UV_PROJECT_ENVIRONMENT=/app/.venv
+
+WORKDIR /app
+
+# Install deps first (cached layer) using only the lockfiles.
+COPY pyproject.toml uv.lock .python-version ./
+RUN --mount=type=cache,target=/root/.cache/uv \
+    uv sync --frozen --no-dev --no-install-project
+
+# --- Runtime: slim image + WeasyPrint system libraries -------------------------
+FROM python:3.13-slim AS runtime
+
+# WeasyPrint needs pango/cairo/gdk-pixbuf + fonts to render PDFs.
+RUN apt-get update && apt-get install -y --no-install-recommends \
+        libpango-1.0-0 \
+        libpangocairo-1.0-0 \
+        libcairo2 \
+        libgdk-pixbuf-2.0-0 \
+        libffi8 \
+        fonts-dejavu-core \
+        fonts-liberation \
+    && rm -rf /var/lib/apt/lists/*
+
+ENV PATH="/app/.venv/bin:$PATH" \
+    PYTHONUNBUFFERED=1 \
+    PYTHONDONTWRITEBYTECODE=1 \
+    DJANGO_SETTINGS_MODULE=config.settings
+
+WORKDIR /app
+
+# Copy the pre-built virtualenv from the builder, then the app source.
+COPY --from=builder /app/.venv /app/.venv
+COPY . .
+
+RUN chmod +x entrypoint.sh
+
+EXPOSE 8000
+ENTRYPOINT ["./entrypoint.sh"]
+CMD ["gunicorn", "config.wsgi:application", "--bind", "0.0.0.0:8000", "--workers", "3"]