Feature request: option for loop label on its own line

I'd like the option to have loop labels on their own line. Something like the example below?

Though perhaps the possible values should be "AlwaysSameLine", "PreferSameLine", "PreferSeparateLine" -- I haven't checked if/how rustfmt currently breaks lines when the label and/or loop expression are very long.

label_style

Label style for control flow constructs.

• Default value: "AlwaysSameLine"
• Possible values: "AlwaysSameLine", "PreferSeparateLine"

"AlwaysSameLine" (default):

fn lorem() {
    let ipsum = 'label1: loop {
        //body
    }

    'label2: for something_long in some_lengthy_selection() {
        // body
    }
}

"PreferSeparateLine":

fn lorem() {
    let ipsum = 'label1: loop {
        //body
    }

    'label2:
    for something_long in some_lengthy_selection() {
        // body
    }
}

No files, tests, or entry points are named. First inspect rustfmt's existing label formatting and configuration handling, then clarify the allowed label_style values and line-breaking rules. Done should include the requested option, formatting matching the examples, and tests covering both styles.