[3.13] gh-123177: Fix prompt for wrapped lines in pyrepl (GH-123324) (#123327)

gh-123177: Fix prompt for wrapped lines in pyrepl (GH-123324)

When display lines above the cursor come from the cache, the first line
to not come from the cache may be a wrapped line, starting half way
through a logical line in the buffer. Detect and handle this case to
avoid accidentally drawing a stray prompt in the middle of a logical
line.
(cherry picked from commit 602fcf97df1665538d4e9841f9dc6bc33e38bece)

Co-authored-by: Matt Wozniski <mwozniski@bloomberg.net>