[FIX] Stop the HUD animating after the shape retracts

Talkify/CoreHUD/HUDStage.swift

@@ -18,7 +18,8 @@ final class HUDStage {
   /// How long the retract animation needs before the panel can order out.
   /// A perceptual duration rather than the spring's settling time, per
   /// WWDC23 "Animate with springs": don't wait for settling.
-  private static let dismissDuration = Duration.milliseconds(350)
+  /// Internal so a test can wait out the retract rather than guess at it.
+  static let dismissDuration = Duration.milliseconds(350)
   private static let messageDuration = Duration.seconds(2)
 
   /// Who holds the shape. `message` is its own occupant rather than a mode of
@@ -148,6 +149,10 @@ final class HUDStage {
       dictationContent.isDismissing = false
       dictationContent.text = ""
       dictationContent.volatileText = ""
+      // The shaping caption outlived the shape: it is what decides whether
+      // the label is mounted, and the label animates every frame while it is.
+      dictationContent.shapingName = nil
+      dictationContent.shapingChoiceLabel = nil
       dropContent.mode = .none
       dropContent.heldIcon = nil
       dropContent.transcript = nil

Talkify/Dictation/HUD/DictationHUDShellView.swift

@@ -173,6 +173,7 @@ struct DictationHUDShellView: View {
           palette: settings.glowPalette,
           scale: metrics.scale,
           activity: label.activity,
+          isRevealed: content.isRevealed,
           reduceMotion: reduceMotion
         )
         .frame(height: metrics.shapingBandHeight)

Talkify/Dictation/HUD/HUDShapingLabel.swift

@@ -30,6 +30,11 @@ struct HUDShapingLabel: View {
   let palette: HUDGlowPalette
   let scale: CGFloat
   let activity: Activity
+  /// False once the shape has retracted. The timeline pauses with it, the
+  /// way every other visual here pauses when its session is not live: a
+  /// running timeline redraws the shader every frame whether or not the
+  /// panel is on screen.
+  let isRevealed: Bool
   let reduceMotion: Bool
 
   @State private var start = Date()
@@ -58,7 +63,7 @@ struct HUDShapingLabel: View {
         .minimumScaleFactor(0.6)
         .foregroundStyle(Color(palette.statusAccent).opacity(0.85))
     } else {
-      TimelineView(.animation) { context in
+      TimelineView(.animation(paused: !isRevealed)) { context in
         let elapsed = context.date.timeIntervalSince(start)
         Text(text)
           .font(font)

TalkifyTests/HUDPlaceholderTests.swift

@@ -147,6 +147,32 @@ struct HUDPlaceholderTests {
     )
   }
 
+  /// The shaping caption decides whether the HUD mounts a label that
+  /// animates every frame, so state left behind after the shape retracts
+  /// costs about 20% of a CPU for as long as the app stays open.
+  @Test func retractingClearsTheShapingCaption() async throws {
+    let store = AppSettings.previewStore()
+    store.voiceVisual = .waveform
+    let stage = HUDStage(settings: store)
+    let hud = DictationHUDController(stage: stage, settings: store)
+
+    hud.showListening(on: CGDirectDisplayID?.none, isLatched: false, settings: session(store))
+    hud.showLiveText("some words")
+    hud.showShaping(with: "Tighten grammar")
+    #expect(stage.dictationContent.shapingName != nil)
+
+    hud.hide()
+    // An event wait, not a time bound. Sleeping for the retract plus a margin
+    // passed alone and failed under a parallel run, which is the flake #82 and
+    // #116 were about; this budget only spends itself on a broken run.
+    for _ in 0..<400 where stage.dictationContent.shapingName != nil {
+      try await Task.sleep(for: .milliseconds(5))
+    }
+
+    #expect(stage.dictationContent.shapingName == nil, "the caption outlived the shape")
+    #expect(stage.dictationContent.shapingChoiceLabel == nil)
+  }
+
   /// The words being rewritten are not a placeholder, so the shaping phase
   /// leaves them where they are.
   @Test func theShapingPhaseKeepsARealDraft() {