Function compute_dynamic_gediis_weight 

pub fn compute_dynamic_gediis_weight(
    energies: &VecDeque<f64>,
    displacements: &VecDeque<f64>,
) -> f64

Computes dynamic GEDIIS weight based on energy trend.

Returns weight in [0.0, 0.98] for blending GDIIS and GEDIIS.