feat(apple): the gamepad UI comes to tvOS - focus-driven, with real session controls

The console UI now runs on tvOS through the NATIVE focus engine: carousel
cards and settings rows are focusable Buttons (Siri Remote and pads both
navigate; imperative scrollTo replaces the drop-prone scrollPosition binding),
while iOS/macOS keep the 60 Hz poll untouched - on tvOS it carries only what
focus has no concept of: X/Y screen actions and left/right value adjust with
the poll's dominant-axis feel (onMoveCommand proved input-source-dependent:
keyboard intercepted, pad dpad not -> double steps). Text entry uses the
system fullscreen keyboard (TVTextEntry); pairing + library present as covers
under the launcher; the game library defaults ON; settings values slide a
quiet 14 pt in the step's direction.

Session controls: controller/remote input routes EXCLUSIVELY through
GameController during a stream (GCEventViewController, interaction disabled) -
a pad's B no longer doubles as a UIKit menu press that ended sessions
mid-game. Deliberate exits only: the cross-client escape chord (hold
L1+R1+Start+Select 1.5 s - pf-client-core's contract, now implemented on all
Apple platforms) and holding the remote's Back >= 1 s; the start-of-stream
banner (now also on tvOS) teaches both. The Siri Remote's touch surface
drives the host pointer - press = left click, Play/Pause = right click,
release-tail jumps gated so motion stays truly relative.

tvOS 26 regressions fixed at the root: the app-wide brand tint rendered every
unfocused control as a blank pill (tint dropped on tvOS) and the 17 pt root
font shrank the whole platform (29 pt there), plus 10-foot sizing across host
cards, the gamepad screens, and the stats HUD (whose misleading "Press Menu"
hint is gone). Acknowledgements scrolls by focus-sized chunks and Menu pops
instead of suspending; full-width focusSections make the home actions
reachable from any column. The presenter defaults to stage-3 glass pacing on
tvOS (a 60 Hz panel fed a 60 fps stream is the sticky-FIFO worst case behind
the 50 ms display stage) and is pickable from the gamepad settings; HDR
capability advertises from AVPlayer.eligibleForHDRPlayback instead of the
current mode's EDR headroom, so an SDR home screen no longer hides an HDR TV.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

clients/apple/Sources/PunktfunkClient/Settings/AcknowledgementsView.swift

@@ -1,13 +1,25 @@
 import PunktfunkKit
 import SwiftUI
 
-/// Open-source acknowledgements: punktfunk's own license (MIT OR Apache-2.0) followed by the
+/// Open-source acknowledgements: Punktfunk's own license (MIT OR Apache-2.0) followed by the
 /// third-party software notices. Used as a pushed view on iOS/tvOS and a preferences tab on macOS.
 struct AcknowledgementsView: View {
     private var version: String? {
         Bundle.main.infoDictionary?["CFBundleShortVersionString"] as? String
     }
 
+    // TV-legible sizes for the explicitly-sized text; the in-hand sizes elsewhere. (The license
+    // walls use relative system styles, which already scale per platform.)
+    #if os(tvOS)
+    private static let titleFont: CGFloat = 36
+    private static let headlineFont: CGFloat = 26
+    private static let captionFont: CGFloat = 20
+    #else
+    private static let titleFont: CGFloat = 22
+    private static let headlineFont: CGFloat = 17
+    private static let captionFont: CGFloat = 12
+    #endif
+
     var body: some View {
         ScrollView {
             // Top-level LazyVStack so the third-party-notices chunks (Licenses.thirdPartyNoticesChunks,
@@ -16,42 +28,40 @@ struct AcknowledgementsView: View {
             // notice chunks visually continuous; the header block carries its own spacing + bottom pad.
             LazyVStack(alignment: .leading, spacing: 0) {
                 VStack(alignment: .leading, spacing: 18) {
-                    Text("punktfunk")
-                        .font(.geist(22, .bold, relativeTo: .title2))
+                    Text("Punktfunk")
+                        .font(.geist(Self.titleFont, .bold, relativeTo: .title2))
                     if let version {
                         Text("Version \(version)")
-                            .font(.geist(12, relativeTo: .caption))
+                            .font(.geist(Self.captionFont, relativeTo: .caption))
                             .foregroundStyle(.secondary)
                     }
-                    Text(Licenses.appLicense)
+                    LicenseWall(text: Licenses.appLicense)
                         .font(.caption.monospaced())
-                        .modifier(SelectableText())
 
                     Divider()
 
                     Text("Bundled font")
-                        .font(.geist(17, .semibold, relativeTo: .headline))
-                    Text("punktfunk ships the Geist typeface (Geist Sans), "
+                        .font(.geist(Self.headlineFont, .semibold, relativeTo: .headline))
+                    Text("Punktfunk ships the Geist typeface (Geist Sans), "
                         + "© The Geist Project Authors / Vercel, used under the SIL Open Font "
                         + "License 1.1.")
-                        .font(.geist(12, relativeTo: .caption))
+                        .font(.geist(Self.captionFont, relativeTo: .caption))
                         .foregroundStyle(.secondary)
                     if !Licenses.fontLicense.isEmpty {
-                        Text(Licenses.fontLicense)
+                        LicenseWall(text: Licenses.fontLicense)
                             .font(.caption2.monospaced())
-                            .modifier(SelectableText())
                     }
 
                     Divider()
 
                     Text("Third-party software")
-                        .font(.geist(17, .semibold, relativeTo: .headline))
+                        .font(.geist(Self.headlineFont, .semibold, relativeTo: .headline))
                     Text(
-                        "punktfunk uses the open-source components below, each under its own license. "
+                        "Punktfunk uses the open-source components below, each under its own license. "
                             + "On some platforms FFmpeg is additionally bundled under the LGPL v2.1+ "
                             + "(dynamically linked, replaceable)."
                     )
-                    .font(.geist(12, relativeTo: .caption))
+                    .font(.geist(Self.captionFont, relativeTo: .caption))
                     .foregroundStyle(.secondary)
                 }
                 .frame(maxWidth: .infinity, alignment: .leading)
@@ -62,6 +72,7 @@ struct AcknowledgementsView: View {
                         .font(.caption2.monospaced())
                         .frame(maxWidth: .infinity, alignment: .leading)
                         .modifier(SelectableText())
+                        .modifier(TVFocusable())
                 }
             }
             .frame(maxWidth: 900, alignment: .leading)
@@ -85,3 +96,40 @@ private struct SelectableText: ViewModifier {
         #endif
     }
 }
+
+/// Focus IS scrolling on tvOS: with nothing focusable in this pushed screen the license wall
+/// couldn't move at all, and a Menu press had nothing inside the NavigationStack to route
+/// through — it suspended the whole app instead of popping. Plain (non-interactive) focusability
+/// on every license/notice chunk fixes both; a chunk is sized to about two thirds of a screen
+/// (see Licenses.chunked), so each focus step reads as a page turn. The chunks must be SMALL
+/// focus stops all the way down — one tall focusable block would strand focus at its top and the
+/// next stop could sit past the LazyVStack's instantiation window.
+private struct TVFocusable: ViewModifier {
+    func body(content: Content) -> some View {
+        #if os(tvOS)
+            content.focusable()
+        #else
+            content
+        #endif
+    }
+}
+
+/// One license wall: a single selectable Text on touch/desktop; on tvOS, focus-page-sized
+/// chunks (see TVFocusable). The caller's `.font` cascades into either form.
+private struct LicenseWall: View {
+    let text: String
+
+    var body: some View {
+        #if os(tvOS)
+        let chunks = Licenses.chunked(text)
+        ForEach(chunks.indices, id: \.self) { i in
+            Text(chunks[i])
+                .frame(maxWidth: .infinity, alignment: .leading)
+                .modifier(TVFocusable())
+        }
+        #else
+        Text(text)
+            .modifier(SelectableText())
+        #endif
+    }
+}