Fix Windows binary utility discovery on Arm64 - #2586

What changed

• Prefer the CTK bin/compute-sanitizer.bat launcher, with compute-sanitizer/compute-sanitizer.exe as the compatibility fallback.
• Resolve standalone Nsight Systems to the native machine target only: target-windows-x64/nsys.exe on x64 or target-windows-armv8/nsys.exe on Arm64. There is no cross-architecture fallback.
• Prefer the standalone Nsight Compute ncu.bat launcher, then fall back to the native machine binary: target/windows-desktop-win7-x64/ncu.exe on x64 or target/windows-desktop-win10-t23x-a64/ncu.exe on Arm64.
• Detect the Windows machine architecture independently of the Python interpreter architecture, and route the existing nsight-sys / nsight-compute aliases through the same rules.

Binary layout survey

The existing IS_WINDOWS macro is intentionally unchanged.

Backward compatibility

• CUDA 13.3 remains supported on Windows x64 through the unchanged core-tool paths and the x64 Nsight direct-binary paths.
• CUDA 13.3 is not treated as a Windows Arm64 installation; Windows Arm64 support starts with CUDA 13.4.
• Existing wheel and Conda search locations retain their priority before system-product discovery.

Testing

• pixi run pytest tests/: 1296 passed, 4 skipped.
• Scoped pre-commit checks, Ruff formatting/lint, and mypy-pathfinder: passed.