Add a way to fine-tune the movement of the adjuster sliders.

This could be through use of the scroll wheel, or by holding a keybind, such as Shift, while dragging the slider.

The issue does not name files, tests, or an entry point. Start by locating the adjuster slider implementation and its input handling, then compare the proposed scroll-wheel or Shift-drag behavior with existing controls; it is done when slider movement can be fine-tuned through a documented interaction and the behavior works consistently.

Written by the indexing model from the issue text.