fix(abacus): use --config flag for phonopy 4.1.0 load mode compatibility

phonopy 4.1.0 ignores positional conf file arguments when in 'load mode'
(triggered by phonopy_disp.yaml). This caused band.yaml/mesh.yaml to not
be generated during the Post step for ABACUS phonon and gruneisen properties.

Fix: pass band.conf explicitly via --config flag, which phonopy 4.1.0
correctly reads as a configuration file even in load mode.

Tested with Cu FCC (ABACUS DFT, 2x2x2 supercell):
- phonon: band.yaml + band.dat + mesh.yaml generated successfully
- gruneisen: FORCE_CONSTANTS + mesh.yaml (3 volumes) generated successfully

Author: Letian88

apex/core/property/Gruneisen.py

@@ -963,7 +963,7 @@ def _ensure_abacus_volume_outputs(
                 if not os.path.isfile("FORCE_CONSTANTS"):
                     raise FileNotFoundError(f"FORCE_CONSTANTS was not created in {helper_dir}")
                 if not os.path.isfile("mesh.yaml"):
-                    subprocess.check_call(Phonon.phonopy_command("band.conf"), shell=True)
+                    subprocess.check_call(Phonon.phonopy_command("phonopy_disp.yaml --config band.conf"), shell=True)
                     self._write_band_dat()
             finally:
                 os.chdir(cwd)

apex/core/property/Phonon.py

@@ -622,7 +622,7 @@ def _compute_lower(self, output_file, all_tasks, all_res):
                     if not os.path.exists("FORCE_SETS"):
                         raise FileNotFoundError("FORCE_SETS was not created")
                     print('FORCE_SETS is created')
-                    subprocess.check_call(self.phonopy_command("band.conf"), shell=True)
+                    subprocess.check_call(self.phonopy_command("phonopy_disp.yaml --config band.conf"), shell=True)
                     self.write_band_dat()
 
                 elif self.inter_param["type"] == 'vasp':