Add ROADMAP pinpoint #255 summarizing the safe subset of hikaMaeng/Sigrid Jin's web-search provider work to adopt later.\n\nReviewed fork commits 262405e, bd11289, fa93cd3, 5f2540a, 7f34d91, and 535be97 from https://github.com/hikaMaeng/claw-code. This deliberately preserves attribution and avoids a blind cherry-pick because the cross-crate provider/spec/config/banner changes need a dedicated implementation lane with tests.