WIP: Update todos automatically

What does this MR do?

Allows todos to update automatically whilst on the todos page.

This will render new todos as updates come in and remove todos as they change state, depending on the todos tab selected.

Are there points in the code the reviewer needs to double check?

WIP

Why was this MR needed?

Because todos are super useful so we should make them even easier to use.

What are the relevant issue numbers?

Closes #14594 (closed).

Screenshots (if relevant)

WIP