Migrate pynvml to cuda.core.system

[mdboom]

This migrates from pynvml.py to the new Cython/cybind-based cuda.core.system.

I was unable to get my local development set up for testing this one, so it's untested.

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[pentschev]

/ok to test 3b9b740

[pentschev]

/ok to test 408fe66

[pentschev]

@mdboom there seems to be some style issues, could you try to automatically fix them with pre-commit install / pre-commit run -a?

[mdboom]

/ok to test 4e248fc

[pentschev]

/ok to test 4e248fc

[pentschev]

Unfortunately you're not part of the rapidsai org, so I think you have no power for triggering testing.

[pentschev]

/ok to test 9dfabb5

[pentschev]

@mdboom there are errors occurring that I think are legit issues, see here for example:

 │ │ Traceback (most recent call last):
 │ │   File "$SRC_DIR/conda_build_script.py", line 1, in <module>
 │ │     import ucxx
 │ │   File "$PREFIX/lib/python3.14/site-packages/ucxx/__init__.py", line 63, in <module>
 │ │     device_count = system.Device.get_device_count()
 │ │   File "cuda/core/system/_device.pyx", line 410, in cuda.core.system._device.Device.get_device_count
 │ │   File "cuda/core/system/_nvml_context.pxd", line 43, in cuda.core.system._nvml_context.initialize
 │ │   File "cuda/core/system/_nvml_context.pyx", line 32, in cuda.core.system._nvml_context._initialize
 │ │   File "cuda/core/system/_nvml_context.pyx", line 42, in cuda.core.system._nvml_context._initialize
 │ │   File "cuda/bindings/nvml.pyx", line 20860, in cuda.bindings.nvml.init_v2
 │ │   File "cuda/bindings/nvml.pyx", line 20866, in cuda.bindings.nvml.init_v2
 │ │     __status__ = nvmlInit_v2()
 │ │   File "cuda/bindings/cynvml.pyx", line 15, in cuda.bindings.cynvml.nvmlInit_v2
 │ │   File "cuda/bindings/_internal/nvml.pyx", line 3892, in cuda.bindings._internal.nvml._nvmlInit_v2
 │ │   File "cuda/bindings/_internal/nvml.pyx", line 2832, in cuda.bindings._internal.nvml._check_or_init_nvml
 │ │     return _init_nvml()
 │ │   File "cuda/bindings/_internal/nvml.pyx", line 417, in cuda.bindings._internal.nvml._init_nvml
 │ │     with gil, __symbol_lock:
 │ │   File "cuda/bindings/_internal/nvml.pyx", line 427, in cuda.bindings._internal.nvml._init_nvml
 │ │     handle = load_library()
 │ │   File "cuda/bindings/_internal/nvml.pyx", line 409, in cuda.bindings._internal.nvml.load_library
 │ │     cdef uintptr_t handle = load_nvidia_dynamic_lib("nvml")._handle_uint
 │ │   File "$PREFIX/lib/python3.14/site-packages/cuda/pathfinder/_dynamic_libs/load_nvidia_dynamic_lib.py", line 303, in load_nvidia_dynamic_lib
 │ │     return _load_lib_no_cache(libname)
 │ │   File "$PREFIX/lib/python3.14/site-packages/cuda/pathfinder/_dynamic_libs/load_nvidia_dynamic_lib.py", line 158, in _load_lib_no_cache
 │ │     return _load_driver_lib_no_cache(desc)
 │ │   File "$PREFIX/lib/python3.14/site-packages/cuda/pathfinder/_dynamic_libs/load_nvidia_dynamic_lib.py", line 71, in _load_driver_lib_no_cache
 │ │     raise DynamicLibNotFoundError(
 │ │     ...<2 lines>...
 │ │     )
 │ │ cuda.pathfinder._dynamic_libs.load_dl_common.DynamicLibNotFoundError: "nvml" is an NVIDIA driver library and can only be found via system search. Ensure the NVIDIA display driver is installed.

Are we supposed to bring NVML from conda to satisfy this?