<img class="op-uc-image op-uc-image_inline" src="/api/v3/attachments/920682/content">

Rework the component structure based on the wireframe above.

Begin of the insertion_Note:End of the insertion Begin of the deletion Note:End of the deletion the wireframe annotation naming has drifted relative to the current code and planned implementation. In particular, this PR series is not introducing a Begin of the insertionseparate_ `_BucketsComponent_`_;End of the insertion Begin of the deletion separate `BucketsComponent`;End of the deletion the Begin of the insertionfuture_ `_BacklogComponent_` _isEnd of the insertion Begin of the deletion future `BacklogComponent` isEnd of the deletion still expected to own the backlog header, bucket-list composition, and inbox composition. Claude Design is currently unavailable, so the diagram itself has not yet been Begin of the insertionupdated._End of the insertion Begin of the deletion updated.End of the deletion

Maintenance checklist:

Begin of the insertion* End of the insertion Begin of the deletion -End of the deletion [x] Create `WorkPackageCardBoxComponent`
Begin of the insertion* End of the insertion Begin of the deletion -End of the deletion [x] Create `WorkPackageCardComponent`
Begin of the insertion* End of the insertion Begin of the deletion -End of the deletion [x] Wire up `SprintComponent` to use `WorkPackageCardBoxComponent` (implementation to validate `WorkPackageCardBox` API)
Begin of the insertion* End of the insertion Begin of the deletion -End of the deletion [x] Rename `BacklogBuckets*Component` to `BucketComponent` (replaces #22886)
Begin of the insertion* End of the insertion Begin of the deletion -End of the deletion [x] Rename `New*Component`/`New*Form` to `*Component`/`*Form`
Begin of the insertion* End of the insertion Begin of the deletion -End of the deletion [x] Rename `BacklogsComponent` to `BacklogComponent` and keep ownership of the backlog header, bucket-list composition, and inbox composition
Begin of the insertion* End of the insertion Begin of the deletion -End of the deletion [ ] Extract `SprintsComponent` from `backlog/_backlog_list.html.erb` Begin of the insertion&mdash; split out as #74143End of the insertion
Begin of the insertion* End of the insertion Begin of the deletion -End of the deletion [x] Wire up `BucketComponent` to use `WorkPackageCardBoxComponent`
Begin of the insertion* [x]End of the insertion Begin of the deletion - [ ]End of the deletion Wire up `InboxComponent` to use `WorkPackageCardBoxComponent`
Begin of the insertion* End of the insertion Begin of the deletion -End of the deletion [ ] Extract a polymorphic container adapter for shared card primitives Begin of the insertion&mdash; split out as #74554
* [ ] Rename and consolidate Backlogs row-menu components (`InboxMenuComponent` / `StoryMenuListComponent`) &mdash; tracked in #74555 (depends on #74554)End of the insertion