Move copyright to the top of files.

tools/format.sh

@@ -8,7 +8,7 @@ for file in $files
 do
   if ! grep -q Copyright $file
   then
-    cat $file ./tools/license_headers.cpp > $file.new && mv $file.new $file
+    cat ./tools/license_headers.cpp $file > $file.new && mv $file.new $file
   fi
 done
 

tools/license_headers.cpp

@@ -1,4 +1,4 @@
-
 // Copyright 2023 Arthur Sonzogni. All rights reserved.
 // Use of this source code is governed by the MIT license that can be found in
 // the LICENSE file.
+