fix(memdb): align _run.sh with CLI-passed args convention

_run.sh hardcoded --instance/--log-level while also forwarding "$@",
so core's services.yaml args produced a duplicate --instance and
boost program_options aborted startup. Now pure "$@" passthrough,
matching db2/ca/captcha2; binary defaults keep manual runs unchanged.

memdb/_run.sh

@@ -1,4 +1,5 @@
 #!/bin/bash
 set -e
 cd "$(dirname "$0")"
-exec ./build/memdb --instance "${INSTANCE:-memdb}" --log-level "${LOG_LEVEL:-info}" "$@"
+# 配置全部经 CLI 传递（core/services.yaml 的 args 声明），与 db2/ca/captcha2 的 _run.sh 惯例一致
+exec ./build/memdb "$@"