Video/general search is login-walled for anonymous sessions, but the Users
tab (/api/search/user) returns public account records without a redirect, so
this exposes the one reliably-unblocked search path. A keyword yields
TikTokProfileItems (name, followers, bio, verification), deduped per query,
capped, and degraded to an ErrorItem when a query is empty/withheld.
Reuses the browser capture (generalized over XHR markers + extractor) and the
shared profile item shape. Billed per account on a new TIKTOK_USER meter
(TIKTOK_MICROS_PER_USER), surfaced on the chat subagent alongside tiktok.scrape.
