Search current active indexed knowledge

Semantic lookup in current active knowledge (up to twenty chunks), including returned sourceId/chunkId for get_knowledge_source/get_knowledge_chunk. Omitted scope filters search the whole connected business; propertyIds selects properties and includeGlobal controls shared knowledge (default true when scoped). This may call the embedding provider. mode=fallback_all means a bounded unranked fallback, not a successful semantic match; totalActive is an eligible count, not returned count. This differs from the runtime planner/scanner and never reproduces a saved answer. Use get_conversation_answer_trace for saved evidence before a new lookup. Inactive knowledge and asset-only uploads are excluded. Required permission: knowledge:read. Connected business only; no tenant override.