Demonstrate queued binary transfer (transferFile) in the Sundial example app

[leogdion]

Epic: brightdigit/AtLeast#182
Depends on: #82 (queued transports) and brightdigit/SundialKitStream#12 (stream routing, for the Stream variant)

Demonstrate queued binary delivery in both demo variants of Examples/Sundial. No new message type needed — Sundial_Demo_ColorMessage / Sundial_Demo_ComplexMessage already conform to BinaryMessagable. This is the example's first use of SendOptions.

Tasks

• Sources/Shared/Models/TransportMethod.swift — add a .queuedFile ("Queued (file)") case alongside the existing transports.
• Combine variant — Sources/SundialDemoCombine/{ViewModels/MessageLabViewModel,Views/MessageLabView}.swift: control that sends the current message with send(message, options: [.queued]).
• Stream variant — Sources/SundialDemoStream/{ViewModels/StreamMessageLabViewModel,Views/StreamMessageLabView}.swift: same .queued send path. Receive side already arrives via typedMessageStream (no change).
• Sources/Shared/Views/MessageHistoryRow.swift — add a transport badge/color for .file.
• Verify: swift run --package-path Examples/Sundial SundialDemoStream / ... SundialDemoCombine.

[leogdion]

Closing as not planned.

The queued transports (transferUserInfo / transferFile) were abandoned and removed from the atleast-beta.6 branches (the pre-rewrite state is preserved at backup/atleast-beta.6-queued). With no .queued / transferFile API there is nothing to demonstrate, so this example-app demo won't be built. Depends-on #82 (queued transports) is also being closed as not planned. See epic brightdigit/AtLeast#182.