docs(components): Update Menu documentation

[taylorvnoj]

Why Is This Changing?

Menu docs were out of sync with the current composable API. The docs page still surfaced deprecated items API examples in some places.
We also want Menu to follow the newer colocated packages/components/src/<Component>/docs example pattern already used by other components.

What Is Changing?

Updated Menu documentation to center the composable API and clarify current guidance around Menu.Trigger, Menu.Content, grouping, deprecated wrappers, and legacy items usage.

Moved Menu example components into packages/components/src/Menu/docs/, updated Menu stories to render those extracted examples, and wired the docs page to explicit Canvas code={...} examples.

Also updated the site-level quick example in packages/site/src/content/Menu/index.tsx so it uses the composable API instead of the deprecated items API.

Consumer Impact

• Impact: None
• Action required: None
• Breaking change: No

Validation

Make sure the Docs page renders actual code examples:

Before

After

NOTE: I know it's referencing ForwardRef in a few places. It's a Storybook source-generation issue. There is currently not a fix (that I'm aware of) that won't impact runtime behaviour. This ForwardRef issue also impacts the props page (not displaying Menu.Item in the list of subcomponents) and will also be an issue for components like Autocomplete, Tabs, etc. There is planned follow up here in general for our documentation.

Docs site Canvas uses composable Menu:

Implement tab has up to date documentation for composable Menu:

Reviewer Notes

Changes can be
tested via Pre-release

---

In Atlantis we use Github's built in pull request reviews.

[cloudflare-workers-and-pages]

Deploying atlantis with    Cloudflare Pages

Latest commit:	44a0e5e
Status:	✅  Deploy successful!
Preview URL:	https://9931e0ed.atlantis.pages.dev
Branch Preview URL:	https://job-164255-menu-eng-docs.atlantis.pages.dev

View logs