Small platform lifecycle services for Craft applications. Application state, settings, palettes, document policy and native command routing remain in their current owners. Defaults add no third-party dependencies. Enable only the services a host uses.

Feature	Shared responsibility
default	Typed dialog outcomes; no backend or toolkit.
`dialogs`	Reserve waiting workers before eager UI-thread native picker creation; serial requests, failure delivery and completion wakeups. The backend factory belongs to the app.
`egui`	Combine with `dialogs` for the deferred-close guard.

Native dialogs

dialogs::wait_prepared(create, deliver) reserves the worker first. Call it on the native UI thread. create must call pick_file, save_file, or the equivalent backend method before returning its future. Putting that call inside an async block delays native sheet creation until the worker polls it. Worker reservation failure never opens the sheet. No live picker has a timeout.

NativeDialogs<Request, Answer> provides an optional serial queue. Pump it on the event-loop thread before consuming answers and after code that can request a picker. Replies become visible only after the pump releases transport ownership, so a continuation can enqueue the next picker. Dropping a stale reply does not release the actual picker. A host-specific preflight is optional; it runs off-thread and must be bounded. Unknown capability permits a picker. Proven absence may request an application-owned fallback. Custom save-format sheets and portal choices remain intact.

Outcome::Selected, explicit Cancelled, Failed and Indeterminate have different evidence. An rfd None is Indeterminate; it cannot prove user cancellation rather than backend failure. Disconnected workers are failures. Apps own localization, document identity/revision checks, filters, actual save receipts, chained continuations and the decision to close.

Retain the actual parent window through queued requests, preflight, the native picker AND any unconsumed application continuation. DeferredClose::update cancels close during pending work and returns a request to retry the application's normal close policy afterward. It never grants permission to discard work. Run those guards before craft_quit::on_close_request in App::logic.

Integration

Enable only the services a host uses. Applications retain palettes, settings, document identity, close policy, filters, names, MIME types and native command routing. Existing craft-settings, craft-atomic, craft-print, craft-docpath and craft-quit remain canonical.