[lldb] Add column sorting to IOHandlerPicker
This patch lets the user sort the picker's rows by pressing `s`, which
cycles through each column in ascending then descending order before
returning to the original order. A column whose values are all integers
compares numerically, and other columns compare as strings. Ties keep
their original relative order, and the cursor moves back to the top after
each sort so the new order is visible.
The column header shows which column is sorted and in which direction, and
each column reserves room for that indicator so it doesn't shift the
layout.
Assisted-by: Claude
Signed-off-by: Med Ismail Bennani <ismail@bennani.ma>
