issue: https://linear.app/comm/issue/ENG-4897/[web]-warnings-in-message-search-modal
when I did the following:

1. Search for a word
2. Scroll down
3. Clear the search query

I was seeing warnings on the console:

socket sent error data isn't of type T
erverError: data isn't of type T
    at InflightRequests.resolveRequestsForMessage (inflight-requests.js:142:139)
    at WebSocket.eval (socket.react.js:170:24)

This was because when the query was cleared queries.current[threadID] was undefined, instead of an empty string. So code in useSearchMessages didn't handle it correctly. This is fixed by this diff, as getQuery returns
queries.current[threadID] ?? ''. useSearchMessages then decieds not to call the server, but return right away.

checked that in the scenario decribed in the summary the error does not appear. Checked that it is possible to fetch messages, and loda more by scrollng down.