Closes#27385
Builds on #27604 so that `vim::OtherEnd` works in visual block mode.
This is accomplished by reversing the order of active selections in the
buffer when the user hit `o`, so that the cursor moves diagonally across
the selection. The current behavior is preserved for `shift-o`, which is
how the cursors behave in vim.
We'll close#27604 since this encapsulates that change, but if you'd
prefer to take only the visual block motion component, we'll keep the
branch for #27604 open.
Test case: growing a box down and to the right, other ending, followed
by growing and shrinking the box:
https://github.com/user-attachments/assets/1df544e1-efce-4354-b354-bbfec007a7df
Test case: growing a box up and to the left, other ending, followed by
growing and shrinking the box:
https://github.com/user-attachments/assets/2f6d7729-c63a-4486-960b-23474c2e507a
Release Notes:
- Improved visual block mode when cursor is at beginning of selection
- Improved visual block mode so that `o` and `shift-o` reach parity with
vim
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Co-authored-by: KyleBarton <kjbarton4@gmail.com>