Function callback_3

tests/test-scheduler-basic-thorough.cpp:210–213

* @brief Third test callback for complex scenarios * * Additional callback for testing multiple task coordination. */

 * Additional callback for testing multiple task coordination.
 */
void callback_3() {
    callback_counter++;
    test_output.push_back("callback_3");
}

/**
 * @brief Multi-step callback for yield testing - step 1