fix: add missing accessor methods to DescrptBlockRepformers

The env_mat_stat code calls descriptor.get_rcut_smth() and
descriptor.get_env_protection() during compute_input_stats, but
DescrptBlockRepformers only had the attributes without accessor
methods, causing AttributeError when training DPA2 models.

Author: Han Wang

deepmd/dpmodel/descriptor/repformers.py

@@ -345,6 +345,14 @@ def get_rcut(self) -> float:
         """Returns the cut-off radius."""
         return self.rcut
 
+    def get_rcut_smth(self) -> float:
+        """Returns the radius where the neighbor information starts to smoothly decay to 0."""
+        return self.rcut_smth
+
+    def get_env_protection(self) -> float:
+        """Returns the protection of building environment matrix."""
+        return self.env_protection
+
     def get_nsel(self) -> int:
         """Returns the number of selected atoms in the cut-off radius."""
         return sum(self.sel)