Guard optional Jenkins vars in database import and export

scripts/jenkins-checkout-source.sh

@@ -7,6 +7,10 @@ COMMIT_HASH="${COMMIT_HASH:-}"
 GIT_REMOTE_URL="${GIT_REMOTE_URL:-}"
 SOURCE_COMMIT_FILE="${SOURCE_COMMIT_FILE:-.jenkins-source-commit}"
 
+# Windows PowerShell 5.1 的 UTF-8 输出可能带 BOM；下游参数校验前先剥离不可见字节。
+SOURCE_BRANCH="$(printf "%s" "${SOURCE_BRANCH}" | sed $'s/^\xef\xbb\xbf//' | tr -d '\r\n')"
+COMMIT_HASH="$(printf "%s" "${COMMIT_HASH}" | sed $'s/^\xef\xbb\xbf//' | tr -d '\r\n')"
+
 if [[ ! "${SOURCE_BRANCH}" =~ ^[0-9A-Za-z._/-]+$ ]]; then
   echo "[jenkins-checkout-source] SOURCE_BRANCH 只能包含数字、字母、点、下划线、短横线和斜杠: ${SOURCE_BRANCH}" >&2
   exit 1