feat(clients): Wake-on-LAN in apple/linux/windows/android/decky

Each client learns a host's MAC from the mDNS `mac` TXT while it's awake, persists it on the saved-host record, and — when reconnecting to an offline host — sends a magic packet before connecting, plus an explicit "Wake host" action. Apple wraps the C-ABI; linux/windows call the core fn directly (linux also gains a --wake CLI mode); android via a new nativeWakeOnLan JNI export (the mDNS browse record gains a 7th mac field); decky shells out to the linux client's --wake before launching the stream.

iOS/tvOS need the managed com.apple.developer.networking.multicast entitlement (pending Apple approval), so the wake path + UI are gated off via PunktfunkConnection.wakeOnLANAvailable and the entitlement is commented out — keeping iOS/tvOS releasable. MAC-learning stays active on every platform so it lights up the moment it's ungated. macOS works today.

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

clients/linux/src/app.rs

@@ -142,6 +142,11 @@ pub fn run() -> glib::ExitCode {
     if let Some(target) = crate::cli::arg_value("--library") {
         return crate::cli::headless_library(&target);
     }
+    // Headless Wake-on-LAN (no GTK window): `--wake host[:port]`. The Decky wrapper calls this
+    // before the stream launch so a sleeping host is up by the time `--connect` runs.
+    if crate::cli::arg_value("--wake").is_some() {
+        return crate::cli::cli_wake();
+    }
     let mut builder = adw::Application::builder().application_id(APP_ID);
     // Screenshot mode launches the app once per scene back-to-back; NON_UNIQUE keeps each
     // launch its own primary instance instead of forwarding to a still-registered name.