Function forces_bohr_to_angstrom 

pub fn forces_bohr_to_angstrom(forces: &DVector<f64>) -> DVector<f64>

Convert forces from Hartree/Bohr to Hartree/Angstrom.

Forces have units of energy/length. To convert from Ha/Bohr to Ha/Å:

F(Ha/Å) = F(Ha/Bohr) × (1 Bohr / 0.529177 Å) = F(Ha/Bohr) × ANGSTROM_TO_BOHR

This ensures forces are consistent with coordinates stored in Angstrom.