Improve framerate of stabilizer
This change aims to improve the framerate of the stabilizer visual
feedback.
- Perform delayed paint during KisToolFreehandHelper::paint (pointer event) and use a timer for backup.
- Removed the stabilizerDelayedPaintInterval config option.
- Added the stabilizerDelayedPaint config option for disabling the delayed painting,
CCBUG: 369349
Maniphest Tasks: T6440
Differential Revision: https://phabricator.kde.org/D6534