[discussion] Add Tour component (onboarding, feature discovery)?

*⚠️ Info: This issue is for product research, to gather community input. In this [base-ui repo](https://github.com/mui/base-ui) we are, currently, focused on the core set of components needed to create a great design system, so the probability we build this in this repo is very low.*

## Summary

## Examples in other libraries

- https://ui.nuxt.com/docs/composables/use-tour
- https://github.com/nilbuild/driver.js
- https://github.com/gilbarbara/react-joyride
- https://github.com/uixmat/onborda (with Shadcn UI example)
- https://saas-ui.dev/docs/components/engagement/tour
- https://github.com/shipshapecode/shepherd
- https://frigade.com/engage#components
- https://www.command.ai/docs/nudges/nudges/tours/overview/

*([internal benchmark](https://www.notion.so/mui-org/x-Tour-component-35ccbfe7b6608037bbb8d8ed40298236))*

## Motivation

Unclear. We had some requests in https://github.com/mui/mui-x/issues/13933 for this but never that much. There is some room for API in Base UI since https://www.onborda.dev/docs/card exists for Shadcn UI, but I can't help myself wonder, is this UI for the pre-AI era? Why would anyone want this? In any case, a placeholder issue will help get more clarity on whether the community needs this or not.

- User requests:
- https://x.com/auduongtuan/status/2041517545015111756
- https://x.com/mhmdev64/status/2042634956464140338
- UI library requests:
- https://github.com/shadcn-ui/ui/issues/999
- https://github.com/mui/mui-x/issues/13933