fix: use Aliyun pip mirror, add timeout for xls2ddl install

build.sh

@@ -55,8 +55,13 @@ python3 -m venv "${VENV}" --clear
 PIP="${VENV}/bin/pip"
 PYTHON="${VENV}/bin/python"
 "${PIP}" install --upgrade pip setuptools wheel -q
-# 先安装 xls2ddl (spec 要求, 用于 DDL 生成和数据导入)
-"${PIP}" install xls2ddl -q 2>/dev/null || true
+# 配置 pip 国内镜像 (阿里云)
+"${PIP}" config set global.index-url https://mirrors.aliyun.com/pypi/simple/ 2>/dev/null || true
+"${PIP}" install --upgrade pip setuptools wheel -q
+# 安装 xls2ddl (DDL 生成工具)
+"${PIP}" install xls2ddl -q --timeout=30 2>/dev/null || {
+    red "  WARN: xls2ddl install failed (PyPI unreachable?), skip"
+}
 green "  OK"
 
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