Function high_priority_callback

tests/test-scheduler-priority.cpp:131–136

* @brief High priority task callback - simulates critical priority work */

 * @brief High priority task callback - simulates critical priority work
 */
void high_priority_callback() {
    priority_callback_counter++;
    priority_test_output.push_back("high_priority_executed");
    priority_execution_times[priority_execution_index++] = millis();
    std::cout << "High priority task executed at " << millis() << "ms" << std::endl;
}

/**
 * @brief Priority test callback that uses currentScheduler() and currentTask()