@Nested
    @DisplayName("Mock Behavior Verification Tests")
    class MockBehaviorTests {

        @Test
        @DisplayName("Should verify all interface methods can be mocked")
        void testAllMethodsCanBeMocked() {
            // Setup all mock behaviors
            when(mockReferralData.getExpiration()).thenReturn(1000L);
            when(mockReferralData.getPathConsumed()).thenReturn(10);