[Dugongue]

Adds a constructive phase-exact compiler for changed supplier charts, with one rank-d Gaussian call and explicit native affine/phase adapters. Complete single and paired transvection-neighbor algorithms reduce a nine-bit local search from 261,632 nonfixed axes to 1,022 distinct changed charts; distance-one paired neighborhoods have 2,043 representatives. Includes universal proofs, exact finite replay and all-input compensated scalar retiming.

No new κ is claimed. The requested full-profile improvement was not found. The package marks the task partial, preserves frozen round-3 inputs and every ownership/phase/endpoint/compiler obligation, and explains why the finite inversion checks in recent #4813/#4818 do not yet exhibit a priced all-width supplier. The separate #4814 ordinary BIT saving is credited and distinguished from the complex/selected frontier.

Validation: Python 3.12 standard-library replay normally and with -O; portable C++20 completeness tests on all 2,448 Lagrangians through dimension 4, literal tariff and inverse checks, byte-identical graph regeneration, package metadata/source-pin and committed-byte checks. Hosted Linux CI and a fresh Lean kernel audit are not claimed. Local history is shallow, so no full source-history audit is claimed.

Credits: Cao Yifan #4610; Cinna Davis #4690/#4672; retained native caller #4713/#4630/#4635; Yiyang #4710; BIT source #4760 and ai-nanachi #4814 with rohanarun #185 and #199/#204 predecessors; partial interfaces #4703/#4797 and prior dossier #4792. Standard Clifford synthesis is credited to Bravyi–Maslov and earlier Bruhat work. Prepared by Dugongue with OpenAI Codex and three agents. Selected frontier unchanged.

Discovery base: 624de9d. Final upstream checkpoint and branch parent: 9e33ecf; guides, priority revision 7 and selected-result certificate unchanged.