How do ViewThatFits and AnyLayout differ, and which one preserves state when the arrangement changes?

Predict first

What re-appears after the switch, and which child does ViewThatFits choose?

@Observable final class Driver { var wide = true }
let driver = Driver()
nonisolated(unsafe) var tokens = 0
final class Token { let id: Int; init() { tokens += 1; id = tokens } }
struct Item: View {
    let name: String
    @State private var token = Token()
    var body: some View { Color.gray.frame(width: 50, height: 20).onAppear { note("\(name) appears (token \(token.id))") } }
}
struct WithAnyLayout: View {
    var body: some View {
        let layout = driver.wide ? AnyLayout(HStackLayout()) : AnyLayout(VStackLayout())
        layout { Item(name: "p"); Item(name: "q") }
    }
}
struct WithBranch: View {
    var body: some View {
        if driver.wide { HStack { Item(name: "p"); Item(name: "q") } }
        else { VStack { Item(name: "p"); Item(name: "q") } }
    }
}
_ = show(WithAnyLayout()); log = []
driver.wide = false; spin()
print("AnyLayout:", log.joined(separator: ", ")); log = []
tokens = 0; driver.wide = true
_ = show(WithBranch()); log = []
driver.wide = false; spin()
print("if/else:", log.joined(separator: ", ")); log = []
struct Pick: View {
    let w: CGFloat
    var body: some View {
        ViewThatFits {
            Color.red.frame(width: 250, height: 10).onAppear { note("250") }
            Color.green.frame(width: 150, height: 10).onAppear { note("150") }
            Color.blue.frame(width: 60, height: 10).onAppear { note("60") }
        }.frame(width: w, height: 40)
    }
}
for w in [300.0, 200.0, 100.0, 30.0] { _ = show(Pick(w: w)); print("width \(Int(w)) picks", log.joined()); log = [] }

• AnyLayout: nothing new / if/else: both items appear again with new tokens / picks 250, 150, 60, 60
• AnyLayout re-creates the items
• ViewThatFits picks the first child always