Shift+Enter line breaks in list items are lost on save/reload

Line breaks added via Shift+Enter between ordered (or unordered) list items do not survive a save and reload cycle. The
elements are silently dropped during HTML re-import into the editor.

Steps to reproduce
Create an ordered list with 3 or more items
Place the cursor at the end of a list item
Press Shift+Enter to insert a blank line (line break) between items
Save the form
Reload the page and open the editor again
Expected: The blank line spacing between list items is preserved.

Actual: All Shift+Enter line breaks are stripped. The list items are collapsed back together with no spacing.

Additional detail
With only 2 list items, the line break sometimes persists. With 3 or more items, line breaks are stripped entirely on every reload.

Environment
Lexxy 0.9.5.beta
Rails 8.1
Tested in Chrome (latest)

Reproduce the save and reload cycle with three or more list items, then trace the editor's HTML re-import path where br elements are dropped. Done means Shift+Enter line breaks remain visible between ordered and unordered list items after reload, including the three-item case.

Written by the indexing model from the issue text.