nx_builder_authors_type_search.nx

nx_builder_authors_type_search.nx -- the BUILDER authors the S3 TYPE-DIRECTED SYNTHESIZER (the novel rung: observational-equivalence enumeration over a whitelisted primitive pool). Claude tutored the algorithm (knowledge/specs/2026-06-09-tutoring-code-synthesis-rung1.md PART B); the Builder authors the module; the Engineer compiles+runs it; the gate is 3 HELD-OUT re-derivations (validator threshold / bit-field extract / clamp) each emitted as a real .nx module the Engineer then builds+runs. Anticheat by construction: primitive pool only, retrieval impossible. license_tier: ORIGINAL