more precise cursor positioning

Dependencies

• [2] RJGZD4IN binary search to most natural up/down with proportional fonts
• [3] PRPPZGDY speed up some obvious common cases
• [4] H7OEU6WP experimental approach to combining keyboard and mouse while drawing
• [5] JS6JSYOT online contextual help
• [*] OTIBCAUJ love2d scaffold

Change contents

• replacement in main.lua at line 761
  [2.959]→[2.959:1038](∅→∅)
  − local currx = cursor_x(line, curr)

  − if currx > x-2 and currx < x+2 then
  [2.959]

  [2.1038]
  + local currxmin = cursor_x(line, curr)

  + local currxmax = cursor_x(line, curr+1)

  + if currxmin <= x and x < currxmax then
• replacement in main.lua at line 766
  [3.584]→[2.1057:1079](∅→∅)
  − if currx > x then
  [3.584]

  [2.1079]
  + if currxmin > x then