Add a `<Note>` component to all MDX files in
`docs/modelcontextprotocol-io/` informing readers that the MCP Registry
is currently in preview and that breaking changes or data resets may
occur before general availability.
The note also directs users to report issues on GitHub at
https://github.com/modelcontextprotocol/registry/issues
Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>