caishzh/dsh-hot-search

Resident search index living in the host process: hot_find (fuzzy filename and path match, with frecency and git status), hot_fuzzy (content search that tolerates typos, including in Chinese), hot_grep (literal and regex content search), hot_plan (groups hits per file so a batch of files can be read in order) and hot_stats. One in-memory line index is built once and rebuilt on demand, so a query does not spawn a process.