Extends the previous commit's fix. The only caller (Donate.vue via
apiService.getSponsors()) never sends a username and always relied on the
server-side default, so the parameter had no legitimate use even after
being parameterized — it just let anyone use deflock's server as an
unauthenticated relay onto GitHub's GraphQL API under the server's own
token. Drop it entirely: the route no longer accepts a username
querystring param, and GithubClient.getSponsors() takes no argument,
hardcoding the maintainer's login via MAINTAINER_USERNAME. Keeps the
$username GraphQL-variable parameterization technique so reintroducing a
variable input later can't reintroduce the injection.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Chris Bowles