concat with diagonal option

[jospueyo]

The python implementation of polars allows an option how = "diagonal" in the pl.concat() when DataFrames don't have the same columns. I tried with nodejs-polars but it seems that this is not implemented:

const pl = require('nodejs-polars')

let df1 = pl.DataFrame(
    {
      id: [1, 2, 3, 4, 5],
      fruits: ["banana", "banana", "apple", "apple", "cherry"],
      cars: ["beetle", "audi", "beetle", "beetle", "vw"],
    }
);

let df2 = pl.DataFrame(
    {
        id: [6, 7, 8, 9],
        fruits: ["pear", "peach", "pineapple", "apple"],
        names: ["John", "Jane", "Joe", "Jack"]
    }
)

console.log(pl.concat([df1, df2]), {how: "diagonal"})

//> Error: lengths don't match: unable to vstack, column names don't match: "cars" and "names"

Thank you for this amazing library.