chore: major code cleanup and type safety using phpstan

src/Form/Service/Abstract/AbstractFieldStateProvider.php

@@ -154,7 +154,7 @@ abstract class AbstractFieldStateProvider implements FieldStateProviderInterface
             }
         }
 
-        if (false === empty($attributes)) {
+        if ([] !== $attributes) {
             $stateModifications['attr'] = $attributes;
         }
 
@@ -170,7 +170,7 @@ abstract class AbstractFieldStateProvider implements FieldStateProviderInterface
      */
     public function hasStateConditions(string $fieldName): bool
     {
-        return isset($this->fieldStateConditions[$fieldName]) && !empty($this->fieldStateConditions[$fieldName]);
+        return isset($this->fieldStateConditions[$fieldName]) && [] !== $this->fieldStateConditions[$fieldName];
     }
 
     /**
@@ -210,7 +210,7 @@ abstract class AbstractFieldStateProvider implements FieldStateProviderInterface
 
         foreach (array_keys($this->fieldStateConditions) as $fieldName) {
             $fieldState = $this->getFieldState($fieldName, $bookingDto, $participantIndex, $formData);
-            if (!empty($fieldState)) {
+            if ([] !== $fieldState) {
                 $allStates[$fieldName] = $fieldState;
             }
         }