Add noExtension flag to getFolderContent for cleaner Paths usage

[HeroEyad]

I think this is annoying every time I have to do Path.withoutExtension() manually just so I can use Paths.image() when pushing folder contents to an array.

This PR adds a new noExtension:Bool = false argument to Paths.getFolderContent() to simplify that process. Internally, it uses Path.withoutExtension() to return filenames without their extensions when the flag is set.

Why this helps:

• Makes folder-to-path workflows easier, especially with Paths.image(), Paths.font(), etc. (this would work with easter eggs and such)
• Cuts down repetitive code (Path.withoutExtension(...)).
• Keeps default behavior intact (noExtension = false).

Example usage:

var iconFiles:Array<String> = [];
var icons = Paths.getFolderContent("images/icons", false, false, true); // noExtension = true

for (icon in icons) {
    iconFiles.push(icon);
}

var spr = new FunkinSprite(0,0,Paths.image(FlxG.random.getObject(iconFiles)))
add(spr);
// or make a better use to it idk.

Before: you'd have to strip extensions manually.

Now: just set noExtension to true and you're done.

[HeroEyad]

thank you furo pls dont kill me