feat(HEL-382): 搭建 datahub 底座和盘后正式数据链路

新增独立 xiaobai-datahub 服务（SQLite WAL、Tushare 盘后发布、/v1 契约和管理后台），不改现站页面与数据链路。

Co-authored-by: Cursor <cursoragent@cursor.com>
Co-authored-by: multica-agent <github@multica.ai>

xiaobai-datahub/Dockerfile

@@ -0,0 +1,36 @@
+FROM python:3.12-slim-bookworm
+
+ARG APP_UID=10002
+ARG APP_GID=10002
+
+ENV PYTHONDONTWRITEBYTECODE=1 \
+    PYTHONUNBUFFERED=1 \
+    PYTHONUTF8=1 \
+    PIP_DISABLE_PIP_VERSION_CHECK=1 \
+    TZ=Asia/Shanghai
+
+WORKDIR /app
+
+RUN apt-get update \
+    && DEBIAN_FRONTEND=noninteractive apt-get install -y --no-install-recommends \
+        ca-certificates \
+        tzdata \
+    && groupadd --gid "${APP_GID}" datahub \
+    && useradd --uid "${APP_UID}" --gid "${APP_GID}" --create-home --shell /usr/sbin/nologin datahub \
+    && rm -rf /var/lib/apt/lists/*
+
+COPY requirements.txt ./
+RUN python -m pip install --no-cache-dir -r requirements.txt
+
+COPY --chown=datahub:datahub . .
+RUN mkdir -p /app/data /app/data/backups && chown -R datahub:datahub /app/data
+
+USER datahub
+
+EXPOSE 8766
+STOPSIGNAL SIGINT
+
+HEALTHCHECK --interval=30s --timeout=5s --start-period=20s --retries=3 \
+    CMD ["python", "-c", "import urllib.request; urllib.request.urlopen('http://127.0.0.1:8766/livez', timeout=4).read()"]
+
+CMD ["python", "-u", "server.py", "--host", "0.0.0.0", "--port", "8766"]