Add search that isn't useless

Users need to search <what>. Roughly <n> records, growing to <n>.

Start with the simplest thing that will be good enough at my size, and
tell me the point at which it stops being good enough.

Handle, at minimum: partial words, different capitalisation, extra
whitespace, and a query that matches nothing. Show me the empty state.

Do not reach for a search service unless my numbers actually need it.