* fix(cursor): keep the visual selection whole over characters outside the BMP
The inclusive Nvim end column was turned into an exclusive VSCode one by
adding a single UTF-16 unit. A character outside the BMP is two of them, so
the selection ended in the middle of a surrogate pair and drifted away from
where Nvim had the cursor: moving right over it took two presses and the
selected region no longer matched.
Step over the whole character instead, using its byte length.
Closes#2535
* test(cursor): add visual selection tests for non-BMP characters
* test(cursor): expect the astral pair to be whole in the mixed-character selection
---------
Co-authored-by: wongxy <xiyao.wong@foxmail.com>
dualfrozandwongxy
5cc37c9f0a