Document the new global-only SOUL behavior, add a dedicated use guide, update personality/context/config docs, and fix docs language that still described cwd-local SOUL loading.
- add code-derived reference pages for slash commands, tools, toolsets,
bundled skills, and official optional skills
- document the skin system and link visual theming separately from
conversational personality
- refresh quickstart, configuration, environment variable, and messaging
docs to match current provider, gateway, and browser behavior
- fix stale command, session, and Home Assistant configuration guidance