[App] Add onboarding wizard (#7064)

* [App] Add onboarding wizard

Took 10 minutes

Took 3 minutes

Took 7 minutes

Took 9 minutes

Took 2 minutes

Took 1 minute


Took 7 minutes

* Adjust CI

Took 14 minutes

Took 56 seconds

Took 2 seconds

Took 3 seconds

* Adjust CI again

Took 14 minutes

Took 2 seconds

* Comments and fixes

Took 9 seconds


Took 1 minute

* Rebase.

Took 5 minutes

Took 50 seconds

Took 15 seconds

* Comments.

Took 7 minutes

* CI lol

Took 3 minutes

* CI again lol

Took 4 minutes

* Drop some settings, add some new ones.

Took 19 minutes

* Resize when expanding section

Took 4 minutes

Took 3 minutes

Took 7 minutes

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Co-authored-by: Lukas Brübach <Bruebach.Lukas@bdosecurity.de>

cockatrice/src/interface/widgets/onboarding/step_indicator_widget.cpp

@@ -0,0 +1,84 @@
+#include "step_indicator_widget.h"
+
+#include <QPainter>
+#include <QPainterPath>
+
+StepIndicatorWidget::StepIndicatorWidget(QWidget *parent) : QWidget(parent)
+{
+    setFixedHeight(kDotDiameter + 2 * kVerticalMargin);
+}
+
+void StepIndicatorWidget::setStepCount(int count)
+{
+    stepCount = qMax(0, count);
+    currentStep = qBound(0, currentStep, qMax(0, stepCount - 1));
+    updateGeometry();
+    update();
+}
+
+void StepIndicatorWidget::setCurrentStep(int index)
+{
+    if (stepCount == 0) {
+        return;
+    }
+    currentStep = qBound(0, index, stepCount - 1);
+    update();
+}
+
+QSize StepIndicatorWidget::sizeHint() const
+{
+    return minimumSizeHint();
+}
+
+QSize StepIndicatorWidget::minimumSizeHint() const
+{
+    if (stepCount == 0) {
+        return QSize(0, height());
+    }
+    int width = kActiveDotWidth + (stepCount - 1) * kDotDiameter + (stepCount - 1) * kDotSpacing;
+    return QSize(width, height());
+}
+
+void StepIndicatorWidget::paintEvent(QPaintEvent * /*event*/)
+{
+    if (stepCount == 0) {
+        return;
+    }
+
+    QPainter painter(this);
+    painter.setRenderHint(QPainter::Antialiasing);
+
+    const QColor activeColor = palette().color(QPalette::Highlight);
+
+    // QPalette::Mid alpha-blended against a dark Window background reads as
+    // near-invisible (Mid is itself a dark grey in dark palettes -- see
+    // PaletteGenerator's satShadeLo/Dark roles). WindowText is guaranteed to
+    // contrast against Window in any theme by definition, so alpha-blending
+    // *that* instead keeps the dots visibly dim-but-present in both light and
+    // dark schemes. Same trick PaletteGenerator uses for placeholder text.
+    QColor inactiveColor = palette().color(QPalette::WindowText);
+    inactiveColor.setAlpha(100);
+
+    int totalWidth = 0;
+    for (int i = 0; i < stepCount; ++i) {
+        totalWidth += (i == currentStep) ? kActiveDotWidth : kDotDiameter;
+        if (i > 0) {
+            totalWidth += kDotSpacing;
+        }
+    }
+
+    int x = (width() - totalWidth) / 2;
+    const int y = height() / 2;
+
+    for (int i = 0; i < stepCount; ++i) {
+        const bool active = (i == currentStep);
+        const int dotWidth = active ? kActiveDotWidth : kDotDiameter;
+
+        QPainterPath path;
+        QRectF rect(x, y - kDotDiameter / 2.0, dotWidth, kDotDiameter);
+        path.addRoundedRect(rect, kDotDiameter / 2.0, kDotDiameter / 2.0);
+        painter.fillPath(path, active ? activeColor : inactiveColor);
+
+        x += dotWidth + kDotSpacing;
+    }
+}