CP2K fixes

[janosh]

this PR fixes several issues with running CP2K in orbital transformation (OT) mode which crashes if it finds a KPOINTS file which the current Cp2kInputGenerator does not allow to disable.

it also fixes

• parsing the stress_tensor in

  path = "cp2k_run_dir"
  atomate2.cp2k.schemas.task.TaskDocument.from_directory(path)

  which was previously looking for stress in cp2k.out (which i did not see mentioned in CP2K docs). it now looks for stress_tensor (still using stress as fallback in case i missed something)

• ignoring empty BASIS and POTENTIAL files in "cp2k_run_dir" which previously caused Invalid Element = None in

  atomate2/src/atomate2/cp2k/schemas/calculation.py

  Line 473 in 0a0d47c

  def _get_basis_and_potential_files(dir_name: Path) -> dict[Cp2kObject, DataFile]:

it goes hand in hand with materialsproject/pymatgen#4169 that fixes a number of bugs in pymatgen CP2K modules

pinging @chiang-yuan and @utf

[utf]

This all looks good to me.

[janosh]

thanks @utf. i added more tests for the CP2K powerups and filesystem utils in 4193ed9 and 21b7aca. there wasn't much coverage

[janosh]

failing tests will be fixed by next pymatgen release since materialsproject/pymatgen#4169 was merged. we could install from master in CI or wait for next release

[utf]

Hi @janosh, best to wait for next release to avoid any indeterministic behaviour from the CI.