Crawl replies can be lost — the eternal 'crawling…' spinner (no client timeout, reconnect-dropped invokes, tight dispatch ceiling)

The Curry Foundation crawl finished server-side in 87 seconds — and the tab spun forever anyway. Three gaps stacked: the browser invoke has no deadline, a WS reconnect (e.g. a workspace-service rebuild mid-crawl) silently drops pending invokes, and the 300s dispatch ceiling was one slow team-crawl away from biting (211s observed).