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/packaging/pack-msix.ps1

@@ -72,7 +72,7 @@ New-Item -ItemType Directory -Force -Path (Join-Path $layout 'Assets') | Out-Nul
 # session client the shell spawns for every stream (sibling resolution — see clients/windows/
 # src/spawn.rs); Skia links statically and vulkan-1.dll is a GPU-driver component, so the session
 # adds no DLLs of its own.
-$required = @('punktfunk-client.exe', 'punktfunk-session.exe', 'Microsoft.WindowsAppRuntime.Bootstrap.dll', 'SDL3.dll', 'resources.pri')
+$required = @('punktfunk-client.exe', 'punktfunk-session.exe', 'punktfunk-console.exe', 'Microsoft.WindowsAppRuntime.Bootstrap.dll', 'SDL3.dll', 'resources.pri')
 foreach ($f in $required) {
     $src = Join-Path $TargetDir $f
     if (-not (Test-Path $src)) { throw "missing build artifact '$f' in $TargetDir (did 'cargo build --release' run?)" }