Effect testEffect and it.live

Always use testEffect(...) from packages/opencode/test/lib/effect.ts for Effect services, layers, runtime context, scopes, and platform integrations; use it.live(...) for filesystems, Git, HTTP, sockets, processes, locks, and real time. Prefer actual implementations, explicit test layers, and scoped fixtures/finalizers over mocks, ad hoc managed runtimes, or globals so provisioning, ownership, and cleanup remain visible. Run tests only from the owning package directory.