Problem: Wrong cursor position when entering command line window
Solution: Add check_cursor() command to verify the cursor position
(Hirohito Higashi).
When opening the command-line window with CTRL-F after typing a command
that fills the screen width, the cursor was placed past the end of the
line. Add check_cursor() after setting State to MODE_NORMAL so the
cursor is adjusted to the last character.
Also fix the cmdwin prefix character (e.g. ':') being drawn on wrapped
continuation rows. Draw an empty space instead so that the text
alignment is preserved.
closes: vim/vim#19964c4fe1e958a
Cherry-pick Test_wildmenu_pum() changes from patch 9.1.1995.
Co-authored-by: Hirohito Higashi <h.east.727@gmail.com>
Co-authored-by: Claude Opus 4.6 (1M context) <noreply@anthropic.com>