session-control.test.tsx 1277→381 lines (32→8 cases): legacy-vs-structured precedence, action dispatch, send continuation (idle + busy-queue), failure banner, heartbeat countdown. store/session-control.test.ts 648→472 lines (26→16): ordering/stale-token invariants, method-not-found downgrade, and a gateway-switch wipe test replacing the removed rebind seam tests; the setTimeout-spy 'no timer' test dropped.