fix: remove bad import in NVFP4 diag

tests/unit/test_nvfp4_primitives.py

@@ -105,9 +105,10 @@ def test_nvfp4_primitives():
     else:
         print(f"  ❌ Scale factors are {x_sf.dtype} — unexpected!")
 
-    # Check what the gemm_runner actually passes to the kernel
-    from dsv4.ops.gemm_runner import Nvfp4GemmRunner
-    print(f"  Nvfp4GemmRunner exists: {Nvfp4GemmRunner is not None}")
+    # Check the gemm_runner class name
+    import dsv4.ops.gemm_runner as gr
+    runner_classes = [name for name in dir(gr) if 'unner' in name or 'Gemm' in name]
+    print(f"  gemm_runner classes: {runner_classes}")
 
     print()
     print("=" * 60)