main: tsc fails with TS2315 'FrozenIndex' is not generic (compact-settled-messages.ts:38) #4467

Summary

tsc --noEmit fails on main (seen at 368d2a8 and 2363e44):

packages/coding-agent/src/modes/rpc/compact-settled-messages.ts(38,27): error TS2315: Type 'FrozenIndex' is not generic.

compact-settled-messages.ts:38 declares export type SettledRoot = FrozenIndex<Row>;, but compact-content-index.ts:33 declares FrozenIndex as a non-generic interface ({ base; overrides }). Both files last changed in #4374 (merge e366403). This looks like two branches that each typechecked alone but conflict after the merge.

Expected

npm run check (which runs tsc --noEmit) passes on main.

Acceptance criteria

• tsc --noEmit at the root reports no errors on main.
• SettledRoot and FrozenIndex agree on one shape.