Review found the branch does not compile. `bun check` runs biome before
the per-workspace type check and joins them with `&&`, so a pre-existing
format error on `main` short-circuited the run: `tsgo --noEmit` never
executed, and `bun test` type-strips, so the suite stayed green over eight
type errors. `ServingModel` was used in `turn-recovery.ts` without being
imported, and three `subscribe` closures in the retry-fallback suite lost
the outer narrowing of `session`. Verified now against the workspace check
directly rather than the aggregate.
Codex also found `#fallbackRouted` outliving its session. It said how the
CURRENT model was reached, but nothing reset it when a transcript was
switched or resumed, so a freshly loaded session with no served attribution
yet described its own model with the previous session's routing. It is now
anchored on the session id exactly like the attribution beside it — the two
facts are earned together and expire together — and a session switch
reports the current model without claiming to know how it got there.
The replay-unsafe host stub gained `getSessionId`, which the real
`SessionManager` has always had and the anchoring now calls.
enieuwy
837b1ac0e2