* fix: sort bound text elements to fix text duplication z-index error
* improve & sort groups & add tests
* fix backtracking and discontiguous groups
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Co-authored-by: dwelle <luzar.david@gmail.com>
* naming tweaks
* do not mark local element as duplicate when there's no remote counterpart
* merge instead of overwrite elements when saving to firebase & reconcile local state
* decouple syncing from persistence
* fix ts
* clarify doc
* fix reconciliation not removing duplicates
