feat: add d4r inference engines and Windows parity tooling

Add native K/M/RR inference engines, HIP kernels, replay and validation
harnesses, and Windows DLSS setup and runtime support. Include GPU
profiling tools, build and packaging scripts, platform integration
patches, and implementation documentation.

packaging/windows/WINDOWS_README.txt

@@ -0,0 +1,68 @@
+d4r for Windows: NVIDIA DLSS on AMD Radeon RDNA3 and RDNA4
+===========================================================
+
+d4r runs NVIDIA's own DLSS (DLSS 4 by default) on a Radeon GPU in DirectX 12 games. OptiScaler
+(included) catches the game's upscaler calls and hands them to d4r.
+
+This is an early release. Only the Radeon RX 9070 XT has been tested on real hardware; every other
+GPU in this release is compile-tested. SUPPORTED_GAMES.md in the source repository lists the
+tested games. Expect problems.
+
+What you need
+-------------
+- Windows 11, a Radeon RX 7000 or RX 9000 series GPU, a current AMD Adrenalin driver.
+- A DirectX 12 game without anti-cheat (OptiScaler injects a DLL; it can get an account banned).
+- NVIDIA DLSS files. The ZIP does not include them. Run install.bat to download official, pinned files.
+  It downloads DLSS SR 310.9.1, Ray Reconstruction 310.9.1, and extracts _nvngx.dll from the
+  official NVIDIA 617.14 driver without installing or changing the driver. SR is stored under d4r\dlss;
+  RR is stored separately under d4r\rr so SR startup cannot auto-load an RR feature. It needs internet access
+  and about 1 GiB temporary space. The driver archive and DLSS files are SHA256-verified.
+  NVIDIA license terms apply. Files stay local and outside public d4r packages.
+
+Install
+-------
+1. Extract this ZIP into the folder that holds the game's main .exe. For Unreal Engine games that
+   is <game>\<Project>\Binaries\Win64, next to <Project>-Win64-Shipping.exe.
+   If the folder already has a dxgi.dll or OptiScaler.ini (another OptiScaler install), or a
+   d3d12.dll from a Linux install, move those out first.
+2. Run install.bat and accept the download prompt. Existing d4r DLLs are backed up outside the game
+   folder with their original paths and SHA256 hashes. Verified downloads are cached in
+   %LOCALAPPDATA%\d4r\cache.
+   The Ray Reconstruction DLL is local preparation only; this Windows game backend does not run RR yet.
+3. Optional: check the install. In the game folder, open PowerShell and run
+       powershell -ExecutionPolicy Bypass -File d4r\d4r-check.ps1
+4. Start the game from Steam, Epic or a shortcut as usual. In its graphics settings choose DLSS
+   (or FSR 3.1/XeSS if DLSS is hidden; OptiScaler then feeds DLSS). Keep frame generation off.
+   Press Insert in game for OptiScaler's menu.
+
+The first time DLSS starts, the game can freeze for several minutes while DLSS's GPU kernels are
+compiled. They are cached in %LOCALAPPDATA%\d4r\cache, so later starts are quick.
+
+Settings
+--------
+Edit d4r\d4r.ini (it is commented) and restart the game. Each game has its own copy.
+- Model: E (preset 5), K (11, DLSS 4), L (12) or M (13, DLSS 4.5). E and L set NGX hints only; the standalone engine and L texture kernels are not integrated. Select quality mode in the game.
+- Kernels/NativeFp8: experimental RDNA4 setting. Requires a matching gfx12 native-FP8 M bundle; keep false with the standard FP16 release. Token-lane and hardware-pack builds remain unvalidated on GPU.
+- AsyncInterop, ValidateOutput, Log: for testing and bug reports; the defaults are the tested setting.
+OptiScaler's own settings (overlay, render ratios) are in OptiScaler.ini.
+
+If something goes wrong
+-----------------------
+- Run d4r\d4r-check.ps1: it prints ok / MISSING / note lines with the fix for each problem.
+- d4r\d4r_nvngx.log is rewritten at every launch. A line "d4r: DLSS disabled: ..." says why.
+- DLSS missing in the menu and no d4r_nvngx.log: the files are not next to the game's main .exe.
+- For a bug report run  d4r\d4r-check.ps1 -Report  and send the ZIP it puts on your Desktop,
+  with your GPU, the game, the model and what the image looked like. Logs can contain folder names.
+- Not supported: frame generation, standalone inference engine, DLSS Ray Reconstruction, DirectX 11, Vulkan. E/L preset hints do not establish full Windows feature parity.
+
+Uninstall
+---------
+Delete dxgi.dll, OptiScaler.ini, OptiScaler.log (if present), WINDOWS_README.txt and the d4r folder
+from the game folder. The cache in %LOCALAPPDATA%\d4r can be deleted too. Nothing else was changed.
+
+Licenses
+--------
+d4r is GNU General Public License, version 3 only (GPL-3.0-only). This ZIP also contains ZLUDA (Apache 2.0 or MIT), OptiScaler (GPL 3.0,
+patched; the patches are in the source repository), and AMD's HIP runtime. d4r\licenses has the
+texts. d4r is not affiliated with NVIDIA, AMD or the OptiScaler project. NVIDIA's files are yours
+to supply, under NVIDIA's terms.