feat(clients/windows): all-vendor video pipeline rewrite + app icon + hosts-page tiles

Decode+present rewrite (first real pixels on glass for this client):

- Decode: FFmpeg D3D11VA on NVIDIA/AMD/Intel. get_format now only returns
  AV_PIX_FMT_D3D11 and lets libavcodec build the decode pool from
  hw_device_ctx (hand-built frames contexts failed three different ways:
  NVIDIA rejects DECODER|SHADER_RESOURCE arrays, BindFlags=0 fails texture
  creation, Intel rejects non-128-aligned HEVC surfaces at the first
  SubmitDecoderBuffers). A DXVA profile probe before the hwdevice commits
  hardware-vs-software up front instead of burning the opening IDR;
  extra_hw_frames covers the frames the client holds.
- Present: the decoded slice is copied with ONE display-size-boxed
  CopySubresourceRegion (a planar slice is a single subresource in D3D11;
  the old two-copy D3D12-style code silently no-opped - the black screen)
  into a sampleable NV12/P010 texture, per-plane SRVs + YUV->RGB shaders.
- New dedicated render thread (render.rs): presenting is decoupled from the
  XAML thread; frame-latency-waitable swapchain + SetMaximumFrameLatency(1),
  newest-wins drain after the wait, crossbeam frame channel with pts for a
  capture->presented p50 log.
- HiDPI: pixel-sized buffers + SetMatrixTransform(96/dpi) - was blurry at
  125/150 % scaling.
- Software fallback now feeds the same shaders (swscale -> NV12/P010 planes
  -> two dynamic plane textures); ps_rgba/X2BGR10 path deleted, hw/sw colour
  math identical.
- Adapter selection for hybrid boxes: PUNKTFUNK_ADAPTER > the window's
  monitor's adapter > default; PUNKTFUNK_D3D_DEBUG=1 debug layer.
- Session pump: request_keyframe at start and on hw->sw demotion (infinite
  GOP would otherwise sit on a black screen).

Validated live on the Arc Pro + RTX 3500 Ada laptop against the local
Windows host: 60 fps D3D11VA on both vendors, software path, GUI on glass.

Also: embedded app icon (build.rs winresource + WM_SETICON, MSIX
Square44x44 targetsize assets, pack-msix stages them) and the hosts-page
tile rework (tap-to-connect tiles with sibling overflow menu - fixes
forget-also-connects - in-tile rename editor, add-host modal via root state).

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

Cargo.lock

@@ -770,6 +770,15 @@ dependencies = [
  "itertools 0.10.5",
 ]
 
+[[package]]
+name = "crossbeam-channel"
+version = "0.5.15"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "82b8f8f868b36967f9606790d1903570de9ceaf870a7bf9fbbd3016d636a2cb2"
+dependencies = [
+ "crossbeam-utils",
+]
+
 [[package]]
 name = "crossbeam-deque"
 version = "0.8.6"
@@ -2760,6 +2769,7 @@ version = "0.4.2"
 dependencies = [
  "anyhow",
  "async-channel",
+ "crossbeam-channel",
  "ffmpeg-next",
  "mdns-sd",
  "opus",
@@ -2772,6 +2782,7 @@ dependencies = [
  "wasapi",
  "windows 0.62.2 (git+https://github.com/microsoft/windows-rs?rev=b4129fcc1ae81eec8bf1217539883db821bca3a1)",
  "windows-reactor",
+ "winresource",
 ]
 
 [[package]]
@@ -5106,6 +5117,16 @@ dependencies = [
  "windows-sys 0.61.2",
 ]
 
+[[package]]
+name = "winresource"
+version = "0.1.31"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "0986a8b1d586b7d3e4fe3d9ea39fb451ae22869dcea4aa109d287a374d866087"
+dependencies = [
+ "toml 1.1.2+spec-1.1.0",
+ "version_check",
+]
+
 [[package]]
 name = "wit-bindgen"
 version = "0.57.1"