Align the copyright holder with the rest of the organization

The notice named 'GIFT Framework' / 'gift-framework', neither of which is a
legal entity and both of which predate the migration to Arithmon. The holder
is now the author, as in the six licenses added across the organization. The
year is unchanged: it records first publication, not this edit.

Author: gift-framework

LICENSE

@@ -1,6 +1,6 @@
 MIT License
 
-Copyright (c) 2025 GIFT Framework
+Copyright (c) 2025 Brieuc de La Fournière
 
 Permission is hereby granted, free of charge, to any person obtaining a copy
 of this software and associated documentation files (the "Software"), to deal