Feature request: add support for `additionalTextEdits` in auto-complete

[edwloef]

Used for things like auto-imports.
It seems to already get shown in the completion palette: , however accepting the completion doesn't actually add the auto-import.

[neurocyte]

Could you post a small code sample where I can test this? (rust is fine)

[edwloef]

fn main() {
    _ = HashMap::new();
}

Cursor is just before the ::, the completion should insert

use std::collections::HashMap;

at the top of the file.