Hermes Agent Docs v2026.4.30

Documentation sync for Hermes Agent v0.12.0 / v2026.4.30.\n\nIncludes:\n- v0.12.0 release documentation and changelog updates.\n- Provider/runtime documentation updates for Azure Foundry, LM Studio, MiniMax OAuth, GMI Cloud, Tencent TokenHub, and auxiliary-model routing.\n- Full canonical upstream docs tree coverage under user-guide, features, messaging, developer-guide, guides, reference, integrations, and getting-started paths.\n- Internal documentation link validation with zero missing Markdown/MDX links in the scanned docs set.\n\nPublished from commit 6628092.