Function broadcast

crates/openquant/src/bet_sizing.rs:207–219

(
        values: &[f64],
        len: usize,
        name: &'static str,
    )

    }

    fn broadcast(
        values: &[f64],
        len: usize,
        name: &'static str,
    ) -> Result<Vec<f64>, BetSizingError> {
        if values.len() == len {
            Ok(values.to_vec())
        } else if values.len() == 1 {
            Ok(vec![values[0]; len])
        } else {
            Err(BetSizingError::ShapeMismatch { name, len: values.len(), expected: len })
        }
    }

    let pos_v = broadcast(pos, target_len, "pos")?;
    let max_pos_v = broadcast(max_pos, target_len, "max_pos")?;