Rename GitHub Actions secrets from DOCKER_TOKEN and DOCKER_USERNAME to DOCKERHUB_TOKEN and DOCKERHUB_USERNAME across all Docker image build workflows for improved clarity and explicit Docker Hub identification.
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Co-Authored-By: Claude <noreply@anthropic.com>
- set top-level explicit permissions for each GitHub Actions workflow for improved security and deduplication of permissions.
- add `persist-credentials: false` to actions/checkout for improved security - see https://github.com/actions/checkout#checkout-v4
- update actions/checkout from v4 to v5