feat(apple): tvOS client — third app target, first-lit in the Apple TV simulator

The same app now runs on tvOS (target Punktfunk-tvOS, bundle io.unom.punktfunk.tvos),
validated live against the box: vkcube at 1280x720@60, 60 fps in the Apple TV 4K
simulator, glass HUD with a focusable Disconnect button.

- PunktfunkCore.xcframework grows tvOS device + universal-simulator slices. These are
  TIER-3 Rust targets (no prebuilt std): BUILD_TVOS=1 builds them with nightly and
  -Zbuild-std from rust-src — the full quic stack (quinn/rustls-ring/tokio) compiles
  for tvOS unchanged.
- The UIKit stream view covers iOS AND tvOS, with pointer interaction, pointer lock,
  touch forwarding and InputCapture gated to iOS — tvOS is view-only until gamepad
  capture lands (the natural tvOS input).
- SessionAudio on tvOS: .playback session, no mic (no app-accessible microphone).
- App chrome gates: keyboardShortcut/textSelection/controlSize/statusBarHidden are
  iOS/macOS-only; host cards use the focus-native .card button style on tvOS; the
  Audio settings section hides (system-routed); mode seeding works from the TV screen
  (1920x1080@60).
- Package platforms += .tvOS(.v17); new Xcode target + shared scheme
  (TARGETED_DEVICE_FAMILY 3, local-network usage description included).

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

scripts/build-xcframework.sh

@@ -12,6 +12,7 @@ cd "$(dirname "$0")/.."
 
 TARGETS_MAC=(aarch64-apple-darwin x86_64-apple-darwin)
 BUILD_IOS="${BUILD_IOS:-0}" # BUILD_IOS=1 adds iOS device + simulator slices (rustup targets aarch64-apple-ios{,-sim})
+BUILD_TVOS="${BUILD_TVOS:-0}" # BUILD_TVOS=1 adds tvOS slices — TIER-3 Rust targets: needs `rustup toolchain install nightly` + `rustup component add rust-src --toolchain nightly`
 
 # Deployment targets must match Package.swift's platforms, or every consumer link emits
 # "object file was built for newer macOS version" warnings.
@@ -23,6 +24,15 @@ if [[ "$BUILD_IOS" == "1" ]]; then
     IPHONEOS_DEPLOYMENT_TARGET=17.0 cargo build --release -p punktfunk-core --features quic --target aarch64-apple-ios-sim
     IPHONEOS_DEPLOYMENT_TARGET=17.0 cargo build --release -p punktfunk-core --features quic --target x86_64-apple-ios
 fi
+if [[ "$BUILD_TVOS" == "1" ]]; then
+    # Tier-3 targets: no prebuilt std — nightly + -Zbuild-std compiles it from rust-src.
+    TVOS_DEPLOYMENT_TARGET=17.0 cargo +nightly build --release -p punktfunk-core --features quic \
+        -Z build-std=std,panic_abort --target aarch64-apple-tvos
+    TVOS_DEPLOYMENT_TARGET=17.0 cargo +nightly build --release -p punktfunk-core --features quic \
+        -Z build-std=std,panic_abort --target aarch64-apple-tvos-sim
+    TVOS_DEPLOYMENT_TARGET=17.0 cargo +nightly build --release -p punktfunk-core --features quic \
+        -Z build-std=std,panic_abort --target x86_64-apple-tvos
+fi
 
 STAGE="$(mktemp -d)"
 trap 'rm -rf "$STAGE"' EXIT
@@ -59,6 +69,15 @@ if [[ "$BUILD_IOS" == "1" ]]; then
     ARGS+=(-library target/aarch64-apple-ios/release/libpunktfunk_core.a -headers "$STAGE/include")
     ARGS+=(-library "$STAGE/iossim/libpunktfunk_core.a" -headers "$STAGE/include")
 fi
+if [[ "$BUILD_TVOS" == "1" ]]; then
+    mkdir -p "$STAGE/tvossim"
+    lipo -create \
+        target/aarch64-apple-tvos-sim/release/libpunktfunk_core.a \
+        target/x86_64-apple-tvos/release/libpunktfunk_core.a \
+        -output "$STAGE/tvossim/libpunktfunk_core.a"
+    ARGS+=(-library target/aarch64-apple-tvos/release/libpunktfunk_core.a -headers "$STAGE/include")
+    ARGS+=(-library "$STAGE/tvossim/libpunktfunk_core.a" -headers "$STAGE/include")
+fi
 
 # Cargo does NOT fingerprint MACOSX_DEPLOYMENT_TARGET — units cached from a build without
 # it keep their old minos forever. Refuse to ship anything newer than the package floor