Test coverage begins — and catches a real reconnect bug on day one

augment-it gets its first automated tests: Vitest wired, nine tests green across the transport, the workspace registry, and didi's corpora slab. The headline property test — 'no invoke silently vanishes' — failed first exactly as the registry predicted, and the failure was real: the client reconnect chain died on any refused connection, a live mechanism behind the zombie-session and lost-corpus symptoms. Found by the test, fixed in the transport, now guarded forever.