feat(ui): add Slider widget for value selection

include/Cubed/ui/slider.hpp

@@ -0,0 +1,47 @@
+#pragma once
+
+#include "Cubed/ui/image.hpp"
+#include "Cubed/ui/widget.hpp"
+
+namespace Cubed {
+class Slider : public Widget {
+public:
+    Slider(Widget* parent);
+
+    Slider& set_slider(float* value, const float& min, const float& max);
+
+    Image& set_track();
+
+    Image& set_thumb();
+
+    float width() const override;
+    float height() const override;
+
+    Slider& set_scale(float scale);
+
+    Slider& set_width(float width);
+    Slider& set_height(float h);
+
+    bool handle_mouse_move_event(const MouseMoveEvent& e) override;
+    bool handle_mouse_button_event(const MouseButtonEvent& e) override;
+
+private:
+    void update_value(float mouse_x);
+
+    void on_update(float) override;
+
+    void on_render(Renderer& renderer) override;
+
+    std::unique_ptr<Image> m_track;
+    std::unique_ptr<Image> m_thumb;
+    float m_scale = 1.0f;
+    float m_width = 0.0f;
+    float m_height = 0.0f;
+    float m_xpos = 0.0f;
+    bool m_dragging = false;
+    bool m_inside = false;
+    float* m_value = nullptr;
+    float m_min = 0;
+    float m_max = 0;
+};
+} // namespace Cubed