The README has always said AGPL-3.0 and the repository invites pull
requests, but there was no LICENSE file and composer.json declared
"proprietary". In that state nobody could legally fork or contribute,
and GitHub could not detect a licence at all.
Adds the AGPL-3.0 text — which the licence itself requires be
distributed with the source — and corrects the composer declaration to
AGPL-3.0-or-later.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
