Replaced std::vector with std::set, for automatic sorting in ListScene widget.

And added `ListScene::removeListItem()` function

src/Helpers/DereferenceLessComparator.hpp

@@ -0,0 +1,14 @@
+#pragma once
+
+#include <type_traits>
+
+namespace Bloom {
+    template<typename Type>
+        requires std::is_pointer<Type>::value
+    struct DereferenceLessComparator
+    {
+        constexpr bool operator () (const Type& lhs, const Type& rhs) const {
+            return *lhs < *rhs;
+        }
+    };
+}