SETEX/SETNX/HMSET/GETSET/ZREVRANGE now try their modern equivalents
first (SET with modifiers, HSET, ZRANGE REV). On error, they silently
fall back to the legacy command and set a compat flag to skip the new
protocol on subsequent calls. Also bump shell to v1.5.4.
Co-Authored-By: deepseek-v4-pro[1m] <deepseek-ai@claude-code-best.win>