Add ConfigMaps & Secrets page with diagram - New ConfigMaps-et-Secrets.md (FR): separating config from images, ConfigMap vs Secret, base64 is not encryption, env vars vs mounted files, Secret best practices, manifests (ConfigMap/Secret/Pod), kubectl commands - New images/configmaps-secrets.svg (ConfigMap + Secret -> Pod container) - Add page to Home and _Sidebar; update AGENTS.md page list