feat(client/windows): make the console UI findable, and launchable on its own

Two problems, one feature. The gamepad/couch UI existed but you had to
already know it was there:

- On the hosts page its card only rendered when a controller was CONNECTED,
  so with no pad plugged in there was no visible entry point at all -- the
  only other door being a per-host overflow menu behind a "..." nobody
  opens. The card now always shows, with copy that adapts to whether a pad
  is present, so the feature is findable before you own the hardware.
- There was no way to start it directly. An HTPC or TV box wants the couch
  interface as its first screen, not the desktop shell. "punktfunk-client
  --console" now hands straight off to it (fullscreen unless --windowed),
  which covers shortcuts, Steam entries, autostart and Task Scheduler.

The Start-menu tile needs its own executable: an MSIX <Application> cannot
pass arguments to a full-trust exe, so "punktfunk-client.exe --console" is
not expressible there. punktfunk-console.exe is a ~20-line hand-off to the
session binary's browse mode, staged into the package and given its own
tile ("Punktfunk Console").

Nothing new is implemented behind either door: a bare "--browse" was
already a complete standalone client (host list, discovery, PIN pairing,
settings, Wake-on-LAN, library). It just had no front door.

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

clients/windows/src/main.rs

@@ -76,6 +76,27 @@ fn main() {
         return;
     }
 
+    // `--console`: go straight to the gamepad/couch UI, skipping the WinUI shell entirely —
+    // the HTPC entry point (a Start-menu tile, a Steam shortcut, a startup item). The session
+    // binary's bare `--browse` IS a complete standalone client: host list, discovery, PIN
+    // pairing, settings and Wake-on-LAN, all controller-driven. We just exec it and mirror
+    // its exit code, so anything supervising this process sees the real result.
+    if flag("--console") {
+        let mut cmd = std::process::Command::new(spawn::session_binary());
+        cmd.arg("--browse");
+        // A couch UI is fullscreen unless explicitly told otherwise.
+        if !flag("--windowed") {
+            cmd.arg("--fullscreen");
+        }
+        match cmd.status() {
+            Ok(st) => std::process::exit(st.code().unwrap_or(0)),
+            Err(e) => {
+                eprintln!("could not start the console UI: {e}");
+                std::process::exit(1);
+            }
+        }
+    }
+
     // Windowed (default): the WinUI 3 app owns host selection, settings, and pairing.
     // Framework-dependent deployment: initialize the Windows App SDK runtime before any WinUI
     // call (build.rs stages the bootstrap DLL via windows-reactor-setup).