Reduce max thickness

The thickness slider is fairly small, so it's difficult to make small
adjustments. The max value of the thickness slider is currently 100, which
is actually pretty huge.

Since most common use cases involve smaller pixel values (closer to the
0-10 range, I suspect), reduce the maximum slider value to 25, allowing for
easier fine grained control of the drawing thickness.

Although fine grained control is already possible via the scroll wheel,
this change improves the overall usability of the tool, especially for new
users who many not know that thickness can be adjusted with the scroll
wheel (or for users who don't have a scroll wheel).

src/widgets/capture/capturewidget.cpp

@@ -794,7 +794,7 @@ void CaptureWidget::moveSelection(QPoint p)
 
 void CaptureWidget::updateThickness(int thickness)
 {
-    m_context.thickness = qBound(1, thickness, 100);
+    m_context.thickness = qBound(1, thickness, maxDrawThickness);
 
     QPoint topLeft =
       QGuiAppCurrentScreen().currentScreen()->geometry().topLeft();
@@ -1290,7 +1290,7 @@ void CaptureWidget::removeToolObject(int index)
 
 void CaptureWidget::setDrawThickness(const int& t)
 {
-    m_context.thickness = qBound(1, t, 100);
+    m_context.thickness = qBound(1, t, maxDrawThickness);
     // save draw thickness for text and other tool separately
     if (m_activeButton) {
         if (m_activeButton->tool() &&

src/widgets/panel/sidepanelwidget.cpp

@@ -32,7 +32,7 @@ SidePanelWidget::SidePanelWidget(QPixmap* p, QWidget* parent)
 
     QFormLayout* colorForm = new QFormLayout();
     m_thicknessSlider = new QSlider(Qt::Horizontal);
-    m_thicknessSlider->setRange(1, 100);
+    m_thicknessSlider->setRange(1, maxDrawThickness);
     m_thicknessSlider->setValue(m_thickness);
     m_colorLabel = new QLabel();
     m_colorLabel->setSizePolicy(QSizePolicy::Expanding, QSizePolicy::Fixed);
@@ -105,7 +105,7 @@ void SidePanelWidget::updateColorNoWheel(const QColor& c)
 
 void SidePanelWidget::updateThickness(const int& t)
 {
-    m_thickness = qBound(0, t, 100);
+    m_thickness = qBound(0, t, maxDrawThickness);
     m_thicknessSlider->setValue(m_thickness);
 }
 

src/widgets/panel/sidepanelwidget.h

@@ -14,6 +14,8 @@ class ColorGrabWidget;
 class QColorPickingEventFilter;
 class QSlider;
 
+constexpr int maxDrawThickness = 50;
+
 class SidePanelWidget : public QWidget
 {
     Q_OBJECT