fix: show webcam capture button in Vue renderer

The capture button was added with canvasOnly: true, which prevented
WidgetButton.vue from rendering it in the Vue node renderer. Remove
the flag so the button appears in both renderers.

src/extensions/core/webcamCapture.ts

@@ -108,7 +108,7 @@ app.registerExtension({
       'waiting for camera...',
       'capture',
       capture,
-      { canvasOnly: true }
+      {}
     )
     btn.disabled = true
     btn.serializeValue = () => undefined