How To Set Custom Icon for Control Center Shortcuts

How do I set a custom icon for an app control that appears in Control Shortcuts (swipe down from iOS) ?

Where is the documentation for size and where to put the image, format etc?

Thank you.

Working Code (sfsymbol)

import Foundation
import AppIntents
import SwiftUI
import WidgetKit

// MARK: - Open App Control
@available(iOS 18.0, *)
struct OpenAppControl: ControlWidget {
    let kind: String = "OpenAppControl"
    
    var body: some ControlWidgetConfiguration {
        StaticControlConfiguration(kind: kind, content: {
            ControlWidgetButton(action: OpenAppIntent()) {
                Label("Open The App", systemImage: "clock.fill")
            }
           }
        })
        .displayName("Open The App") // This appears in the shortcuts view
    }
}

Sample Image These apps use their own image. How can I use my own image?