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.

tests/test_model_l.py

@@ -0,0 +1,48 @@
+"""L must retain its unfolded neural math when native surface stores are substituted."""
+import os
+from pathlib import Path
+import subprocess
+import tempfile
+import unittest
+
+ROOT = Path(__file__).resolve().parents[1]
+
+
+class ModelLTests(unittest.TestCase):
+    def test_model_l_config_and_environment_precedence(self):
+        with tempfile.TemporaryDirectory() as directory:
+            ini = Path(directory) / 'd4r.ini'
+            ini.write_text('[DLSS]\nModel = L\n')
+            env = dict(os.environ)
+            env.pop('D4R_DLSS_PRESET', None)
+            cmd = ['python3', str(ROOT / 'scripts/d4r_config.py'), '--config', str(ini)]
+            self.assertIn('export D4R_DLSS_PRESET=12', subprocess.check_output(cmd, env=env, text=True))
+            env['D4R_DLSS_PRESET'] = '11'
+            self.assertNotIn('export D4R_DLSS_PRESET=', subprocess.check_output(cmd, env=env, text=True))
+
+    def test_unfolded_variants_preserve_neural_arithmetic(self):
+        names = ['rrlite_dec0_4x4']
+        for mv in ('mvhi', 'mvlo'):
+            for dynamic_range in ('hdr', 'ldr'):
+                names.append(f'rrlite_enc0_4x4_{mv}_{dynamic_range}')
+                names.extend(f'rrlite_post_{v}_{mv}_{dynamic_range}' for v in ('3_1', '3_2'))
+        math = 'mma.sync.aligned.m16n8k32.row.col.f16.e4m3.e4m3.f16 {%r1, %r2}, {%r3, %r4, %r5, %r6}, {%r7, %r8}, {%r9, %r10};'
+        store = 'sust.b.2d.v2.b16.zero [%rd1, {%r1,%r2}], {%rs1,%rs2};'
+        with tempfile.TemporaryDirectory() as directory:
+            ptx = Path(directory)
+            env = dict(os.environ, D4R_DLSS_PTX_DIR=directory, D4R_SUST_KINDS='b16,p,b32')
+            for name in names:
+                with self.subTest(kernel=name):
+                    (ptx / 'input.ptx').write_text(f'.visible .entry {name}(\n)\n{{\n{math}\n{store}\nret;\n}}\n')
+                    subprocess.run(['python3', str(ROOT / 'kernels/tex/make_ptx.py'), name, str(ptx / 'out.ptx')],
+                                   env=env, check=True, capture_output=True)
+                    output = (ptx / 'out.ptx').read_text()
+                    self.assertIn(math, output)
+                    self.assertNotIn(store, output)
+                    self.assertIn('call d4r_sust_v2b16', output)
+                    self.assertNotIn('d4r_enc0_tail', output)
+                    self.assertNotIn('d4r_dec0_head', output)
+
+
+if __name__ == '__main__':
+    unittest.main()