- `typescript` pinned to `next` (7.1 nightly): stable `7.0.2` panics on `isolatedDeclarations` (native declaration-emit bug). Revert to `*` once TS 7.1 reaches the `latest` tag.
- Dropped the `typescript` programmatic compiler API (not shipped in native TS7); structural checks now parse via `oxc-parser` (`scripts/lib/esast.ts`). Reconsider if TS7 publishes a JS API.
-- Pre-existing: `scripts/build/build.test.ts` "release build parity" fails because release inlines ultra's `implementation` chunk while dev keeps it separate (lazy-boundary divergence). Independent of the toolchain swap; needs an ultra chunking decision.