feat: support Image binding (#4347)

src/element/typeChecks.ts

@@ -85,6 +85,7 @@ export const isBindableElement = (
     (element.type === "rectangle" ||
       element.type === "diamond" ||
       element.type === "ellipse" ||
+      element.type === "image" ||
       element.type === "text")
   );
 };

src/renderer/renderScene.ts

@@ -683,6 +683,7 @@ const renderBindingHighlightForBindableElement = (
   switch (element.type) {
     case "rectangle":
     case "text":
+    case "image":
       strokeRectWithRotation(
         context,
         x1 - padding,