Redesign invalid node indicator (#358)

* nit

* Remove unused code

Gradient can (and should) be impl. directly by caching a CanvasGradient.

* nit

* nit - Refactor

* Remove redundant code

* Add line width & colour options to shape stroke

* Rename drawSelectionBounding to strokeShape

* nit - Doc

* Fix rounded corners not scaling with padding

* Optimise node badge draw

* Redesign invalid node visual indication

Customisable boundary indicator now used, replacing red background.

* Update snapshot

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Co-authored-by: huchenlei <huchenlei@proton.me>

src/LGraphGroup.ts

@@ -183,11 +183,8 @@ export class LGraphGroup implements Positionable, IPinnable {
     ctx.fillText(this.title + (this.pinned ? "📌" : ""), x + padding, y + font_size)
 
     if (LiteGraph.highlight_selected_group && this.selected) {
-      graphCanvas.drawSelectionBounding(ctx, this._bounding, {
-        shape: RenderShape.BOX,
+      graphCanvas.strokeShape(ctx, this._bounding, {
         title_height: this.titleHeight,
-        title_mode: TitleMode.NORMAL_TITLE,
-        fgcolor: this.color,
         padding,
       })
     }