Drop careless-gpu: the [cuda] pip extra install covers GPU and CPU nodes

The installed careless/0.5.4 venv already contains the NVIDIA wheels
([cuda] extra), which need only the node driver and fall back to CPU,
so a separate GPU module and cuda module dep are unnecessary. Revert
careless/build to careless[cuda] to match the actual install.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

careless/modulefile

@@ -7,8 +7,9 @@ module-maintainer   "MX Data <jiaxin.duan@psi.ch>"
 
 module-help     "
 careless: scaling and merging of X-ray diffraction data using
-approximate Bayesian inference (TensorFlow). CPU build; for
-NVIDIA GPU nodes load careless-gpu instead.
+approximate Bayesian inference (TensorFlow). Installed with the
+[cuda] extra: uses NVIDIA GPUs when present (no cuda module
+needed), falls back to CPU otherwise.
 "
 
 setenv          CARELESS_ENV    $PREFIX/venv