Added const variants of Borrow.

src/Memory/NonNullOwnPtr.hpp

@@ -21,6 +21,10 @@ namespace Arbutils::Memory {
 
         inline NonNullBorrowedPtr<T> Borrow() { return NonNullBorrowedPtr<T>(_ptr); }
 
+        inline const NonNullBorrowedPtr<const T> Borrow() const{
+            return NonNullBorrowedPtr<const T>(_ptr);
+        }
+
         T* operator->() noexcept { return _ptr; }
         const T* operator->() const noexcept { return _ptr; }
 

src/Memory/OwnPtr.hpp

@@ -24,6 +24,9 @@ namespace Arbutils::Memory {
         inline BorrowedPtr<T> Borrow(){
             return BorrowedPtr<T>(_ptr);
         }
+        inline const BorrowedPtr<const T> Borrow() const{
+            return BorrowedPtr<const T>(_ptr);
+        }
 
         T* operator->() noexcept { return _ptr; }
         const T* operator->() const noexcept { return _ptr; }