Add a UNUserNotificationCenterDelegate didReceive handler so tapping a notification
is handled inside the running app — activating and bringing the existing window
forward — instead of falling through to default launch behavior, which on macOS
can surface a second process. The approval/transfer UI is driven by core state, so
activating the window reveals any pending approval.
Adds background notifications for the "the thing you were waiting for is
done" moments, alongside the existing incoming-approval-request one:
- a receive finished downloading (receive -> done)
- a receive failed / was interrupted (receive -> failed)
- a share you own failed (send -> failed)
- a receiver finished downloading your share (receiver status completed)
A new TransferNotificationCoordinator observes core state + signals and
publishes these; the decision of which moments notify is a pure function
(plannedTransferNotifications / plannedReceiverNotifications), unit-tested
independently. The first state snapshot only primes existing history as seen
so launch doesn't spam.
Notification permission is now the single source of truth. The in-app
notifications toggle and its decoupled UserDefaults preference are gone;
the Settings section shows an "Allow notifications" button that requests the
OS permission (or deep-links to Settings once decided), and notifications
gate purely on `permission == .granted`.
macOS delivery fixes:
- add a UNUserNotificationCenterDelegate so banners present even while the
app is active (the app window is usually open on macOS)
- present-when-active on macOS, suppress-when-foregrounded on iOS
- reserve the notification id before awaiting publish: the CombineLatest
fired several times and re-added the same identifier, which macOS
coalesces into a silent update with no banner
- LocalNotificationService seeds its permission at init so gating can't
race a not-yet-refreshed .notDetermined
Eight localized title/body strings added (apple-only); the shared
notifications_description copy is generalized from "receive requests" to
"transfer activity".
Add a native SwiftUI VniDrop app (Send/Receive/Settings) talking to the
Rust core via generated UniFFI Swift bindings, plus the uniffi-bindgen
helper crate. iOS uses a TabView, macOS a NavigationSplitView sidebar.
