Add vnasset SDXL generate command

ROCm-safe bfloat16 inference with custom matmul attention.
Automatic output directories, random seed, timing metadata.

pyproject.toml

@@ -0,0 +1,24 @@
+[build-system]
+requires = ["setuptools>=64"]
+build-backend = "setuptools.build_meta"
+
+[project]
+name = "vnassets"
+version = "0.1.0"
+requires-python = ">=3.12"
+dependencies = [
+    "torch",
+    "diffusers",
+    "transformers",
+    "accelerate",
+    "safetensors",
+    "pillow",
+    "pyyaml",
+    "click",
+]
+
+[tool.setuptools.packages.find]
+exclude = ["models*"]
+
+[project.scripts]
+vnasset = "vnassets.cli:main"