Where is the documentation on scripts/plugins?

[growe19]

ArmorPaint 1.0 alpha-6246a99, Windows

Issue description:
Looking for some solid documentation on scripts and plugins so I can create something. I've been attempting all sorts using the hello_world example. And whilst I can get a nice UI there is no functionality because my code doesn't work.

Steps to reproduce:
My code to try and add Layers and Groups from a template quickly:

let plugin = new arm.Plugin();

let handle1 = new zui.Handle();

// Function to create and add layers
function addTemplatedLayers() {
let project = arm.Project.get();

if (project) {
    console.log("Project found.");

    // Create a new group layer
    let groupLayer = new arm.Layer();
    groupLayer.name = "New Group";
    groupLayer.setType(arm.LayerType.Group);
    groupLayer.init();
    
    // Create new paint layers
    let paintLayer = new arm.Layer();
    paintLayer.name = "Paint Layer";
    paintLayer.setType(arm.LayerType.Paint);
    paintLayer.init();

    let fillLayer = new arm.Layer();
    fillLayer.name = "Fill Layer";
    fillLayer.setType(arm.LayerType.Fill);
    fillLayer.init();

    let decalLayer = new arm.Layer();
    decalLayer.name = "Decal Layer";
    decalLayer.setType(arm.LayerType.Decal);
    decalLayer.init();

    // Add layers to the group
    groupLayer.children.push(paintLayer);
    groupLayer.children.push(fillLayer);
    groupLayer.children.push(decalLayer);
    console.log("Added layers to the group.");

    // Add the group to the project's root layer
    project.layerRoot.addChild(groupLayer);
    console.log("Added group to the project's root layer.");

    // Update the project and UI to reflect changes
    project.layerRoot.updateChildren();
    arm.UI.refresh();
    console.log("Updated project and UI.");
} else {
    console.error("No project found.");
}

}

plugin.drawUI = function(ui) {
if (ui.panel(handle1, "Add Templated Layers Plugin")) {
if (ui.button("Add Templated Layers")) {
addTemplatedLayers();
}
}
}