Function run_mix_audio_step

app/workflow/workflow.cpp:903–940

        const auto text_out_option = workflow_optional_string(step, "text_out");
        const auto text_out = text_out_option.has_value()
            ? resolve_workflow_path(*text_out_option, context)
            : step_dir / (id + ".txt");
        if (!text_out.parent_path().empty()) {
            std::filesystem::create_directories(text_out.parent_path());
        }
        std::ofstream out(text_out);
        out << text << "\n";
        context.values[id + ".text_path"] = text_out.string();
        std::cout << "text_out=" << text_out.string() << "\n";
    }
    std::cout << "workflow_step=" << id << "\n";
}

void run_mix_audio_step(
    const engine::io::json::Value & step,
    WorkflowContext & context) {
    const std::string id = workflow_string(step, "id");
    const auto * inputs_value = step.find("inputs");
    if (inputs_value == nullptr || !inputs_value->is_array()) {
        throw std::runtime_error("mix_audio step requires inputs array: " + id);
    }
    std::vector<engine::audio::AudioMixInput> inputs;
    for (const auto & item : inputs_value->as_array()) {
        engine::audio::AudioMixInput input;
        input.audio = engine::audio::read_wav_f32(resolve_workflow_path(workflow_string(item, "path"), context));
        input.gain = static_cast<float>(workflow_optional_number(item, "gain").value_or(1.0));
        if (const auto activity_ref = workflow_optional_string(item, "activity_ref")) {
            input.activity_reference = engine::audio::read_wav_f32(resolve_workflow_path(*activity_ref, context));
            input.activity_threshold_dbfs =
                static_cast<float>(workflow_optional_number(item, "activity_threshold_dbfs").value_or(-40.0));
            input.activity_window_seconds = workflow_optional_number(item, "activity_window_seconds").value_or(0.1);
            input.activity_margin_seconds = workflow_optional_number(item, "activity_margin_seconds").value_or(0.35);
            input.activity_fade_seconds = workflow_optional_number(item, "activity_fade_seconds").value_or(0.03);
        }
        inputs.push_back(std::move(input));
    }
    const bool normalize = workflow_optional_bool(step, "normalize_peak", true);
    const auto mixed = engine::audio::mix_audio_to_reference_shape(inputs, normalize);
    const auto output = resolve_workflow_path(workflow_string(step, "output"), context);
    if (!output.parent_path().empty()) {
        std::filesystem::create_directories(output.parent_path());