[DevTask] Impl. TS strict typing in new widget classes

Widget classes currently pass TS strict checks inside the new modules, but the code added to call them requires strict mode be disabled (or bypassed with assertions). `@ts-expect-error` is being temporarily added to enable strict by default.

┆Issue is synchronized with this [Notion page](https://www.notion.so/Issue-4736-DevTask-Impl-TS-strict-typing-in-new-widget-classes-2476d73d3650810f9ff8ea368cd15333) by [Unito](https://www.unito.io)