feature: generate pdf from actor

src/elements/box.ts

@@ -0,0 +1,22 @@
+import { AbstractElement } from './abstract-element';
+import jsPDF from 'jspdf';
+
+export class Box extends AbstractElement {
+  public w: number;
+  public h: number;
+
+  constructor(x: number, y: number, w: number, h: number) {
+    super(x, y, w);
+    this.w = w;
+    this.h = h;
+  }
+
+  public render(doc: jsPDF, _maxWidth?: number): jsPDF {
+    doc.rect(this.x, this.y, this.w, this.h);
+    return doc;
+  }
+
+  public getHeight(_doc): number {
+    return this.h;
+  }
+}