Let \( A(0, 1) \), \( B(1, 1) \), and \( C(1, 0) \) be the midpoints of the sides of a triangle with incentre at the point \( D \). If the focus of the parabola \( y^2 = 4ax \) passing through \( D \) is \( (\alpha + \beta \sqrt{3}, 0) \), where \( \alpha \) and \( \beta \) are rational numbers, then \( \frac{\alpha}{\beta^2} \) is equal to: