[Tagging] Toast Notifications for changes to tags

[bradenmacdonald]

"As a content author, when I make changes to tags, I want the opportunity to undo those changes"

Acceptance Criteria

1. Toast notifications automatically dismiss after 5 seconds
2. There is only ever one toast shown to the user. It provides a summary of all the changes made in the drawer e.g.
   User removes 1 tag (and its 2 implicit parents): the toast reads “3 tags removed”. Within the next 5 seconds, the user removes another tag (and its 1 implicit parent): the toast text is updated to read: "5 tags removed" Selecting “undo” on the toast would undo both removals.
3. The "Undo" button on the toast works.

Developer Notes

• Screenshots above are for convenience - Figma is the most up-to-date source for mockups. The scale of UI elements seen in the screenshots above may be incorrect.

[ali-hugo]

@bradenmacdonald I noticed this issue has a "pending UX changes" label. It's not easy to imagine how the UX for removing tags will "feel" until we have something clickable to interact with. Would it be ok to refine the UX outlined in this issue at that stage?

[bradenmacdonald]

@ali-hugo Yes, we have deferred this story (and all the editing stories) for now, so that's totally fine.