added new overlay for splits when you hold alt that does nothing yet

src/widgets/helper/splitoverlay.hpp

@@ -0,0 +1,40 @@
+#pragma once
+
+#include "pajlada/signals/signalholder.hpp"
+#include "widgets/basewidget.hpp"
+
+namespace chatterino {
+namespace widgets {
+
+class Split;
+
+class SplitOverlay : public BaseWidget, pajlada::Signals::SignalHolder
+{
+public:
+    explicit SplitOverlay(Split *parent = nullptr);
+
+protected:
+    void paintEvent(QPaintEvent *event) override;
+
+private:
+    enum HoveredElement { None, SplitMove, SplitLeft, SplitRight, SplitUp, SplitDown };
+    HoveredElement hoveredElement = None;
+    Split *split;
+
+    class ButtonEventFilter : public QObject
+    {
+        HoveredElement hoveredElement;
+        SplitOverlay *parent;
+
+    public:
+        ButtonEventFilter(SplitOverlay *parent, HoveredElement hoveredElement);
+
+    protected:
+        bool eventFilter(QObject *watched, QEvent *event) override;
+    };
+
+    friend class ButtonEventFilter;
+};
+
+}  // namespace widgets
+}  // namespace chatterino