fix(z3): guard missing source model in false-optional operation

Replace the broken exception guard (cast never raises and the caught type was
wrong) with an explicit check for the attached source model, and fix the copied
PySAT logger name.

Author: José Ángel Galindo Duarte

flamapy/metamodels/z3_metamodel/operations/z3_false_optional_features.py

@@ -10,7 +10,7 @@
 from flamapy.metamodels.z3_metamodel.models import Z3Model
 
 
-LOGGER = logging.getLogger('PySATFalseOptionalFeatures')
+LOGGER = logging.getLogger('Z3FalseOptionalFeatures')
 
 
 class Z3FalseOptionalFeatures(FalseOptionalFeatures):
@@ -26,11 +26,11 @@ def get_result(self) -> list[Any]:
 
     def execute(self, model: VariabilityModel) -> 'Z3FalseOptionalFeatures':
         z3_model = cast(Z3Model, model)
-        try:
-            feature_model = cast(FeatureModel, model.original_model)
-        except FlamaException:
-            LOGGER.exception("The transformation didn't attach the source model, "
-                             "which is required for this operation.")
+        original_model = getattr(model, 'original_model', None)
+        if original_model is None:
+            raise FlamaException("The transformation didn't attach the source model, "
+                                 "which is required for this operation.")
+        feature_model = cast(FeatureModel, original_model)
         self._result = get_false_optional_features(z3_model, feature_model)
         return self