feat(apple): stage-2 default + pixel-perfect, decode robustness, UI/rumble polish

Stream reliability
- Default to the stage-2 presenter (VTDecompressionSession + CAMetalLayer): it detects
  and recovers a wedged decoder, where stage-1's AVSampleBufferDisplayLayer freezes hard
  on a lost HEVC reference frame with no app-side recovery (confirmed Apple limitation).
  Stage 1 is now a DEBUG-only presenter toggle, plus the automatic no-Metal fallback.
- Stage-2 pixel-perfect: render the drawable at the decoded size (shader stays 1:1 =
  identity) and let the layer's contentsGravity scale via the system compositor — the
  same path stage-1's videoGravity used — instead of scaling in-shader.
- Loss recovery in both pumps is now a persistent awaitingIDR want, retried until an IDR
  actually lands, so a keyframe request swallowed by the throttle can't strand a frozen
  frame; 100 ms keyframe throttle to match the Android path.
- Fix "Publishing changes from within view updates": defer the HostStore writes out of
  the .onChange(of: model.phase) callback.
- Move AVAudioSession setActive/setCategory off the main thread (async on a shared serial
  queue) to stop the UI-stall warning.

Controllers
- Rumble: capped-exponential backoff when the gamecontrollerd.haptics XPC breaks (-4811)
  so a transient server interruption self-heals instead of cascading; playsHapticsOnly so
  a controller engine doesn't join the always-active streaming audio session.
- Host cards: iPad pointer "magnet" hover effect; iPhone press scale + light haptic.

UI / design
- Ship Geist (SIL OFL 1.1) as the app font (bundled OTFs + registration), with the
  license surfaced in Acknowledgements.
- Restructure iOS/iPadOS Settings into a category NavigationSplitView; resolution wheel
  with custom-resolution entry; 10-bit HDR toggle in Display.
- Industrial host-card redesign (left-aligned, bold, brand monogram tiles).

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

clients/apple/Sources/PunktfunkClient/PunktfunkClientApp.swift

@@ -12,20 +12,36 @@ struct PunktfunkClientApp: App {
     @NSApplicationDelegateAdaptor(AppDelegate.self) private var appDelegate
     #endif
 
+    init() {
+        #if os(iOS)
+        // Put Geist on the navigation titles before any bar is built.
+        BrandTheme.apply()
+        #endif
+    }
+
     var body: some Scene {
         WindowGroup("Punktfunk") {
-            #if DEBUG
-            // PUNKTFUNK_SHOT_SCENE=<name> → show that single mock-populated screen full-bleed for
-            // the App Store screenshot capture (tools/screenshots.sh). Normal launch otherwise;
-            // the whole path is absent from Release builds.
-            if let scene = ScreenshotMode.requestedScene {
-                ScreenshotHostView(scene: scene)
-            } else {
+            // Pin the whole app's tint to the brand purple explicitly — the asset-catalog accent
+            // resolution is environment/timing-sensitive and can fall back to system blue. Wraps the
+            // screenshot harness too, so captured screens are on-brand.
+            Group {
+                #if DEBUG
+                // PUNKTFUNK_SHOT_SCENE=<name> → show that single mock-populated screen full-bleed for
+                // the App Store screenshot capture (tools/screenshots.sh). Normal launch otherwise;
+                // the whole path is absent from Release builds.
+                if let scene = ScreenshotMode.requestedScene {
+                    ScreenshotHostView(scene: scene)
+                } else {
+                    ContentView()
+                }
+                #else
                 ContentView()
+                #endif
             }
-            #else
-            ContentView()
-            #endif
+            .tint(.brand)
+            // Geist Sans is the app's typeface. This sets the default for unstyled text and the
+            // form row labels; views that pick an explicit size/weight use `.geist(…)` directly.
+            .font(.geist(17, relativeTo: .body))
         }
         // The Stream menu (Disconnect ⌘D, Show/Hide Statistics ⌘⇧S) — a real menu bar on
         // macOS, hardware-keyboard shortcuts on iPad. tvOS has neither.
@@ -34,7 +50,10 @@ struct PunktfunkClientApp: App {
         #endif
         #if os(macOS)
         Settings {
+            // A separate scene — `.tint` does not cross scene boundaries, so re-apply the brand
+            // tint here or the Preferences window falls back to the (unreliable) asset accent.
             SettingsView()
+                .tint(.brand)
         }
         #endif
     }