Respect annotation processing order

// DO: Process interface annotations before local class annotations
for (SourceClass ifc : sourceClass.getInterfaces()) {
    collectImports(ifc, imports, visited);
}
imports.addAll(sourceClass.getAnnotationAttributes(Import.class.getName(), "value"));

// DO: Validate annotation usage
if (executionPhase == ExecutionPhase.BEFORE_TEST_CLASS && !isClassLevel) {
    throw new IllegalArgumentException("Class-level phase cannot be used on method-level annotation");
}

// Consider explicitly handling bean definition conflicts
if (!isAllowBeanDefinitionOverriding() && existingDefinition != null 
        && !existingDefinition.equals(beanDefinition)) {
    throw new BeanDefinitionOverrideException(beanName, beanDefinition, existingDefinition);
}

// Better approach for single-instance configurers
@Autowired(required = false)
void setAsyncConfigurer(AsyncConfigurer asyncConfigurer) {
    if (asyncConfigurer != null) {
        this.executor = asyncConfigurer::getAsyncExecutor;
        this.exceptionHandler = asyncConfigurer::getAsyncUncaughtExceptionHandler;
    }
}