Salvaged from #50659 by @LeonSGP43 onto current main (the client
resolver was rewritten for strict-selection semantics since the PR;
reapplied the keyless mode as a third client_mode inside the new
resolver). An explicit firecrawl selection with no FIRECRAWL_API_KEY /
FIRECRAWL_API_URL now routes through a minimal REST client (v2 search +
scrape, no Authorization header) instead of erroring. Unconfigured
installs never route here — the keyless path requires the explicit
selection. Fixes#49912.
LeonSGP43
f51e61136a