Address known thread-safety issues in `cuda.core`

[leofang]

In general, cuda.core has a few internal, module-level states that should be guarded by a lock. We haven't done that extensively.

Originally posted by @leofang in #1364 (comment)

[leofang]

Example:

cuda-python/cuda_core/cuda/core/experimental/_launcher.pyx

Lines 20 to 35 in 027ba10

	# TODO: revisit this treatment for py313t builds
	_inited = False
	_use_ex = None
	def _lazy_init():
	global _inited
	if _inited:
	return
	global _use_ex
	# binding availability depends on cuda-python version
	_py_major_minor = get_binding_version()
	_driver_ver = handle_return(driver.cuDriverGetVersion())
	_use_ex = (_driver_ver >= 11080) and (_py_major_minor >= (11, 8))
	_inited = True

[leofang]

Sebastian's comment here is relevant: #1390 (comment)