feat(apple): send a transfer to a device from the share panel

Send to a device now sits alongside the QR code, NFC, and export actions,
since an offer is another way to deliver the same invitation. Picking a
device pushes the existing transfer rather than re-sharing the files.

The picker lists only devices holding a live grant, so nothing offered there
can fail on tap, and it distinguishes accepted from waiting for that device
to open the app.

Also fixes the deprecated SF Symbol and the two Sendable warnings introduced
with the contacts screen: the sections now talk to the model directly rather
than storing view callbacks that a Binding setter has to convert.

apple/VniDrop/Features/Send/SendScreen.swift

@@ -5,6 +5,7 @@ import SFSafeSymbols
 /// with the composer and detail panels as native sheets and delete as an alert.
 struct SendScreen: View {
 	@ObservedObject var model: SendModel
+	@ObservedObject var contacts: ContactsModel
 	let windowClass: WindowClass
 
 	/// Transfer pending an inline (list-level) delete confirmation.
@@ -60,7 +61,7 @@ struct SendScreen: View {
 				onDismissed: model.shareSheetDidDismiss
 			) {
 				if let shareTarget {
-					TransferSharePanel(model: model, transfer: shareTarget)
+					TransferSharePanel(model: model, contacts: contacts, transfer: shareTarget)
 				}
 			}
 		}
@@ -93,7 +94,7 @@ struct SendScreen: View {
 	/// alert attached here so they present from the detail's own context (presenting
 	/// modals from the parent stack while a detail is pushed is unreliable on macOS).
 	private func detailView(for transfer: Transfer) -> some View {
-		TransferDetailsView(model: model, transfer: transfer, events: model.coreState.events)
+		TransferDetailsView(model: model, contacts: contacts, transfer: transfer, events: model.coreState.events)
 			.adaptiveDrawer(
 				isPresented: Binding(get: { model.state.detailPanel != nil }, set: { _ in }),
 				windowClass: windowClass,
@@ -101,7 +102,7 @@ struct SendScreen: View {
 				onDismissed: model.shareSheetDidDismiss
 			) {
 				if let panel = model.state.detailPanel {
-					DetailPanelContent(model: model, transfer: transfer, panel: panel)
+					DetailPanelContent(model: model, contacts: contacts, transfer: transfer, panel: panel)
 				}
 			}
 			.alert(

apple/VniDrop/Features/Send/TransferDetailsView.swift

@@ -6,6 +6,7 @@ import CoreImage.CIFilterBuiltins
 
 struct TransferDetailsView: View {
 	@ObservedObject var model: SendModel
+	@ObservedObject var contacts: ContactsModel
 	let transfer: Transfer
 	let events: [CoreEventModel]
 	@State private var showStopConfirmation = false
@@ -129,6 +130,7 @@ private struct DetailDestination: View {
 
 struct DetailPanelContent: View {
 	@ObservedObject var model: SendModel
+	@ObservedObject var contacts: ContactsModel
 	let transfer: Transfer
 	let panel: TransferDetailPanel
 
@@ -146,7 +148,7 @@ struct DetailPanelContent: View {
 				onAccept: model.acceptReceiver
 			)
 		case .share:
-			TransferSharePanel(model: model, transfer: transfer)
+			TransferSharePanel(model: model, contacts: contacts, transfer: transfer)
 		}
 	}
 }
@@ -296,6 +298,7 @@ private struct ReceiverRow: View {
 struct TransferSharePanel: View {
 	@Environment(\.vniColors) private var colors
 	@ObservedObject var model: SendModel
+	@ObservedObject var contacts: ContactsModel
 	let transfer: Transfer
 
 	var body: some View {
@@ -309,7 +312,7 @@ struct TransferSharePanel: View {
 						.font(VniType.bodySmall).foregroundStyle(colors.foregroundLighter)
 						.frame(maxWidth: .infinity)
 				}
-				ShareActionsView(model: model, transfer: transfer, ticket: ticket)
+				ShareActionsView(model: model, contacts: contacts, transfer: transfer, ticket: ticket)
 			case .preparing:
 				Text(String(localized: L10n.Transfer.eventPreparing)).foregroundStyle(colors.foregroundLighter)
 			case .unavailable:

apple/VniDrop/Features/Send/TransferShareActions.swift

@@ -20,14 +20,25 @@ protocol TransferShareActions: AnyObject {
 struct ShareActionsView: View {
 	@Environment(\.vniColors) private var colors
 	@ObservedObject var model: SendModel
+	@ObservedObject var contacts: ContactsModel
 	let transfer: Transfer
 	let ticket: String
 
 	@State private var actions: TransferShareActions = makePlatformShareActions()
 	@State private var writingNfc = false
+	@State private var choosingDevice = false
 
 	var body: some View {
 		VStack(spacing: 12) {
+			// Sending straight to a remembered device is another way to deliver
+			// this same invitation, so it belongs with the other delivery
+			// methods rather than in a separate flow.
+			if contacts.state.contacts.contains(where: \.canSend) {
+				SecondaryButton(
+					title: String(localized: L10n.Contacts.sendToDevice),
+					action: { choosingDevice = true }
+				)
+			}
 			if actions.nfcAvailability != .hidden {
 				SecondaryButton(
 					title: writingNfc ? String(localized: L10n.Transfer.nfcWaiting) : String(localized: L10n.Button.writeNfc),
@@ -57,5 +68,8 @@ struct ShareActionsView: View {
 			}, enabled: actions.canUseNativeShare)
 		}
 		.onDisappear { actions.cancelNfcWrite() }
+		.sheet(isPresented: $choosingDevice) {
+			DevicePickerSheet(model: contacts, transferId: transfer.transferId)
+		}
 	}
 }