The value o the integral \( \int_{-\pi/4}^{\pi/4} \left( \frac{32\cos^4 x}{1+e^{\sin x}} \right) dx \) is:
\( 4\pi + 2 \)
\( 3\pi + 8 \)
\( 3\pi + 4 \)
\( 4\pi + 3 \)