Introduce OwnedStringView

A managed String which uses RAII to free its contents. It's not a proper string though, since it's read-only.
So it's a StringView... but an owned one.

Can't be copied automatically, must be either moved or copied manually by calling clone() on it.

luna/CMakeLists.txt

@@ -9,6 +9,7 @@ set(FREESTANDING_SOURCES
     src/Bitmap.cpp
     src/Stack.cpp
     src/Alloc.cpp
+    src/OwnedStringView.cpp
 )
 
 set(SOURCES

luna/include/luna/OwnedStringView.h

@@ -0,0 +1,27 @@
+#pragma once
+
+class OwnedStringView
+{
+  public:
+    OwnedStringView(char* c_str);
+    OwnedStringView();
+    OwnedStringView(OwnedStringView&&);
+    OwnedStringView(const OwnedStringView&) = delete;
+    ~OwnedStringView();
+
+    Result<OwnedStringView> clone();
+
+    const char* chars()
+    {
+        return m_string;
+    }
+
+    usize length()
+    {
+        return m_length;
+    }
+
+  private:
+    char* m_string{nullptr};
+    usize m_length{0};
+};

luna/src/OwnedStringView.cpp

@@ -0,0 +1,36 @@
+#include <luna/Alloc.h>
+#include <luna/OwnedStringView.h>
+#include <luna/String.h>
+
+OwnedStringView::OwnedStringView()
+{
+}
+
+OwnedStringView::OwnedStringView(OwnedStringView&& other)
+{
+    m_string = other.m_string;
+    m_length = other.m_length;
+
+    other.m_string = nullptr;
+}
+
+OwnedStringView::OwnedStringView(char* c_str)
+{
+    m_string = c_str;
+
+    if (m_string) { m_length = strlen(m_string); }
+}
+
+OwnedStringView::~OwnedStringView()
+{
+    if (m_string) destroy_array(m_string);
+}
+
+Result<OwnedStringView> OwnedStringView::clone()
+{
+    char* buf = TRY(make_array<char>(m_length + 1));
+
+    memcpy(buf, m_string, m_length + 1);
+
+    return OwnedStringView{buf};
+}