Add built flag and fallback path for unbuilt tries in Search/Has#6

WJiangzhi wants to merge 2 commits into

masterZCT-Studio/ZACLib:masterfrom

codex/ensure-search-and-has-operate-like-replaceZCT-Studio/ZACLib:codex/ensure-search-and-has-operate-like-replaceCopy head branch name to clipboard