* feat: implement drag-and-drop reordering for checklist items
* WIP: Changes before syncing with main
* feat: update drag icon and positioning
* refactor: consolidate checklist item updates into single endpoint
- Remove standalone reorderItem route (now part of updateItem)
- Add optional index parameter to updateItem for reordering
- Change updateItem from PUT to PATCH method
- Add deletedAt IS NULL filter to reorderItem SQL queries
- Follows existing pattern from card.update route
* feat: add optimistic updates
* chore: translations
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Co-authored-by: Henry <henry_ball@hotmail.co.uk>
