Let the curve \( z(1+i)+\bar{z}(1-i)=4 , \; z \in \mathbb{C} \), divide the region \( |z-3|\le 1 \) into two parts of areas \( \alpha \) and \( \beta \). Then \( |\alpha-\beta| \) equals:
\(\displaystyle 1+\frac{\pi}{3} \)
\( \displaystyle1+\frac{\pi}{6} \)
\(\displaystyle 1+\frac{\pi}{2} \)
\(\displaystyle 1+\frac{\pi}{4} \)