Make the first RAG slice executable without risking production data

The Stage 1 foundation now proves provider contracts with mocks and validates PostgreSQL/pgvector ingestion, approval binding, retrieval, reranking, and idempotency using only synthetic data. Live Bailian validation remains gated on rotating the exposed key.

Constraint: The key shown in chat is compromised and cannot be used or committed

Rejected: Mark Stage 1 complete from mock and offline results | real three-model smoke is still required

Confidence: high

Scope-risk: moderate

Reversibility: clean

Directive: Do not enable real-data ingestion until Stage 3 cloud approval and outbound manifest controls are enforced end to end

Tested: make verify; 41 pytest tests; strict mypy; Ruff; Compose config; pinned image build; empty-volume migration; role denial; two idempotent 20-vector seeds; database restart persistence

Not-tested: Live Bailian calls require a newly rotated key; React product UI is not implemented

backend/Dockerfile

@@ -0,0 +1,33 @@
+# syntax=docker/dockerfile:1.7@sha256:a57df69d0ea827fb7266491f2813635de6f17269be881f696fbfdf2d83dda33e
+FROM ghcr.io/astral-sh/uv:0.11.3@sha256:90bbb3c16635e9627f49eec6539f956d70746c409209041800a0280b93152823 AS uv
+
+FROM python:3.12-slim-bookworm@sha256:8a7e7cc04fd3e2bd787f7f24e22d5d119aa590d429b50c95dfe12b3abe52f48b AS runtime
+
+ENV PYTHONUNBUFFERED=1 \
+    PYTHONDONTWRITEBYTECODE=1 \
+    UV_COMPILE_BYTECODE=1 \
+    UV_LINK_MODE=copy \
+    PATH="/app/.venv/bin:$PATH"
+
+RUN groupadd --system --gid 10001 app \
+    && useradd --system --uid 10001 --gid app --home-dir /app app
+
+COPY --from=uv /uv /uvx /bin/
+
+WORKDIR /app
+
+COPY pyproject.toml uv.lock ./
+RUN uv sync --frozen --no-dev --no-install-project
+
+COPY alembic.ini ./
+COPY migrations ./migrations
+COPY app ./app
+COPY README.md ./
+
+RUN uv sync --frozen --no-dev \
+    && chown -R app:app /app
+
+USER app
+EXPOSE 8000
+
+CMD ["python", "-m", "app.main"]