* Introducing fractional indices as part of `element.index`
* Ensuring invalid fractional indices are always synchronized with the array order
* Simplifying reconciliation based on the fractional indices
* Moving reconciliation inside the `@excalidraw/excalidraw` package
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Co-authored-by: Marcel Mraz <marcel@excalidraw.com>
Co-authored-by: dwelle <5153846+dwelle@users.noreply.github.com>