* ci: bump GitHub Actions to Node.js 24 runtimes
Clear Node 20 deprecation warnings on runners by moving workflow
actions to majors that declare node24 (checkout, cache, setup-node,
artifacts, Docker buildx/build-push/qemu/login, github-script,
setup-go, Azure login/helm, create-pull-request, axe-linter).
* fix: release leader lock via ioredis on Redis Cluster
@keyv/redis EVAL can surface unhandled MOVED redirects on cluster,
so resign() logged failure and left LeadingServerUUID set. Use ioredis
for leader election SET NX / GET / Lua (same pattern as principals and
concurrency locks) so cluster redirects are retried and resignation
clears the lock.
