Exercise 1: NavigationStack with a List of Tasks and a Detail Screen — Possible Solution
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struct Task: Identifiable, Hashable {
    let id = UUID()
    let title: String
}

struct TaskDetailView: View {
    let task: Task

    var body: some View {
        Text(task.title)
            .font(.largeTitle)
            .navigationTitle("Task Detail")
    }
}

struct TaskListView: View {
    let tasks: [Task] = [
        Task(title: "Buy groceries"),
        Task(title: "Finish report"),
        Task(title: "Call dentist"),
        Task(title: "Water plants"),
        Task(title: "Read a chapter")
    ]

    var body: some View {
        NavigationStack {
            List(tasks) { task in
                NavigationLink(task.title, value: task)
            }
            .navigationTitle("Tasks")
            .navigationDestination(for: Task.self) { task in
                TaskDetailView(task: task)
            }
        }
    }
}

HOW IT WORKS: Task conforms to both Identifiable (needed for
List(tasks), per Chapter 7) and Hashable (needed for
navigationDestination(for:), per this chapter). Each
NavigationLink(task.title, value: task) displays the task's own title
as tappable row text, and declares task itself as the real value being
navigated with - no destination view is embedded inside the link
itself.

The single .navigationDestination(for: Task.self) modifier, attached
once at the NavigationStack level, is what actually decides what to
show whenever ANY Task value is navigated to from within this stack -
tapping any of the five rows pushes TaskDetailView, correctly
displaying that specific tapped task's own title.

ANSWER: A NavigationStack containing a List of five Task items, each a
NavigationLink(value:), paired with one shared
.navigationDestination(for: Task.self) modifier, correctly pushes a
TaskDetailView showing the specific tapped task's own title whenever
any row is selected.

WHY THIS WORKS AS AN ANSWER
------------------------------
This correctly implements the chapter's own value-based navigation
pattern end to end, with Task satisfying both real protocol
requirements (Identifiable and Hashable) needed for List and
navigationDestination respectively.