Slate v2 Normalization Policy Recovery

Goal

Recover the next honest normalization-policy seam for True Slate RC without pretending the engine already has full legacy schema control.

Current Slice

1. verify the partially-started shouldNormalize hook is worth keeping
2. prove the contract with snapshot-contract.ts before widening the claim
3. keep the hook narrowly scoped to the custom normalizeNode pass
4. update proof and docs only if the code slice survives verification

Notes

• a fake parity hook is worse than a missing hook
• built-in normalization behavior is still separate from this custom pass gate

Result

• shouldNormalize is kept as a narrow pass-level gate over the custom normalizeNode seam
• the custom pass now calls shouldNormalize once per iteration instead of once per entry
• core falls back safely when an older editor instance does not define shouldNormalize
• the contract is proved in snapshot-contract.ts for delegation, pass-level gating, and skip behavior
• docs and the proof ledger are aligned to the narrowed claim

Verification

• yarn test:custom