Function  
 loop
(t: number, action: () => void, maxLoops?: number, waitFirst?: boolean): TimerControllerRun the function every n seconds.
param t- The time to wait in seconds.
param action- The function to run.
param maxLoops- The maximum number of loops to run. If not provided, it will run forever.
param waitFirst- Whether to wait for the first loop to start.
// spawn a butterfly at random position every 1 second
loop(1, () => {
    add([
        sprite("butterfly"),
        pos(rand(vec2(width(), height()))),
        area(),
        "friend",
    ])
})returns A timer controller.
since v2000.0
group Timer