fn neutral_element() -> Self {
        // SAFETY:
        // - `[0, 1, 1]` is a mathematically verified neutral element in Edwards curves.
        // - `unwrap()` is safe because this point is **always valid**.
        let point = Self::new([
            FieldElement::zero(),
            FieldElement::one(),
            FieldElement::one(),
        ]);
        point.unwrap()
    }
Returns the point at infinity (neutral element) in projective coordinates.

# Safety

- The values `[0, 1, 1]` are the **canonical representation** of the neutral element
in the Edwards curve, meaning they are guaranteed to be a valid point.
- `unwrap()` is used because this point is **known** to be valid, so
there is no need for additional runtime checks.
crates/math/src/elliptic_curve/edwards/point.rs