Replace GUI connection startup waits with a cancellable, staged Qt transaction. Observe core endpoints, DNS resolution, TUN device readiness, and runtime survival without nested event-loop waits while preserving the synchronous plugin compatibility path.
Commit runtimes only after every required stage succeeds, reject stale generations, and cover readiness, cancellation, rollback, platform ordering, and controller integration.
Signed-off-by: Loren Eteval <loren.eteval@proton.me>