feat: support unbinding bound text (#4686)

* feat: support unbinding text

* fix unbound text

* move the unbind option next to group action

* use boundTextElement.id when unbinding

* update original text so it takes same bounding box when unbind

* Add spec

* recompute measurements when unbinding

src/actions/index.ts

@@ -80,3 +80,4 @@ export { actionToggleGridMode } from "./actionToggleGridMode";
 export { actionToggleZenMode } from "./actionToggleZenMode";
 
 export { actionToggleStats } from "./actionToggleStats";
+export { actionUnbindText } from "./actionUnbindText";