- Add provideInstance, provideTmpdirInstance to test/fixture/fixture.ts
- Delete test/fixture/instance.ts (withServices no longer needed)
- Rewrite format tests to use provideTmpdirInstance + testEffect (fully Effect-native)
- Effect-native bus tests use provideTmpdirInstance
- Plugin: use bus.subscribeAll() Stream + forkScoped instead of callback facade
- Vcs: use bus.subscribe() Stream + forkScoped instead of acquireRelease callback
- Status: use bus.publish() Effect directly instead of Effect.promise wrapper
- Rewrite Vcs test to use facade functions (shared memoMap ensures singleton Bus)
- Add Bus integration tests for subscribe cleanup and instance disposal
- Add runCallback to makeRuntime (returns interrupt function directly)
- Simplify forkStream to use runCallback instead of runFork + Fiber.interrupt
- Add 6 bus tests covering publish/subscribe, unsubscribe, subscribeAll,
and InstanceDisposed delivery on instance disposal