feat(wave-a): close ADR-011 (SDPO alignment indices) + ADR-012 (review findings)

feat(hints): ADR-009 layered HintGenerator; accepted

Wave 18: 14 backlog items closed + 3-reviewer cross-family review

Wave 16: install ergonomics + gradient evidence + SDPO end-to-end example

Wave 15: 4-angle multi-model self-critique caught 2 math BLOCKERs in primary loss kernels; fixed against upstream byte-for-byte + GSM8K example + ergonomics

Wave 14: close every Wave 13 review finding + 4 documentation files; Wave 14b: real PRIME-RL parity + multi-process DiLoCo convergence