Search Providers as First-Class — Stand Up SearXNG as the New Default for Social Packs; Tavily Stays as a Peer; Per-Row Iteration as the Workflow We're Building Toward

The social packs route through Tavily today, but Tavily is a content-RAG index — wrong substrate for sparse-text JS-rendered social-profile pages. The fix is **not** to swap Tavily out. The fix is to make **search provider** a first-class concern in the architecture, stand SearXNG up as a peer, flip the common-seven social packs so SearXNG becomes their new default, and keep Tavily wired in as a peer for the content-RAG packs/bundles that will want it (deep-research, document extraction, annual-report summarization). The deeper goal — the reason this is more than a refactor — is that the product is being shaped around an **iteration loop**: a user finds a `not_found` or low-confidence response in the by-record triage view, suspects the provider is the issue, and wants to re-fire the same pack against the same row through a different provider (SearXNG → Brave → Google CSE → direct-API connector) until the accurate data surfaces with the fewest API calls. That loop only exists if providers are plural and selectable per-fire.