Progress

• Started review of packages/slate/src/transforms-node/* with source-first diff against legacy.
• Read legacy/current same-path diffs for the full transforms-node family.
• Confirmed one concrete package type regression on setNodes<T> and fixed it.
• Reviewed the rest of the family for the same public-contract narrowing pattern.
• Recovered generic public contracts across the node-transform family on interfaces/editor.ts, index.ts, create-editor.ts, and the transforms-node/* exports.
• Added focused generic-contract coverage in packages/slate/test/transforms-contract.ts.
• Verified slate build and targeted transform tests pass. Site-wide typecheck still has unrelated existing errors in check-lists.tsx and embeds.tsx, but richtext.tsx is clean again.