shutdown

Shuts the SDK down: cancels its in-flight work, releases what it holds, and leaves it uninitialized.

Rarely needed — an SDK initialized in Application.onCreate is meant to live as long as the process. Reach for this only where the SDK's lifetime is genuinely shorter than the app's, or in tests between cases.

Every service obtained before this call becomes unusable, and every accessor on CGS throws InitializationException again until init runs a second time. Downloads already written to disk survive; downloads still in flight do not.