[docs] Move the demo higher in the API TOC

[oliviertassinari]

It might solve these feedback:

https://mui-org.slack.com/archives/C041SDSF32L/p1668804057511509

When I'm landing on the API page, I usually have to scroll to the bottom of the page to then go to the demo (it happens to me quite often). Maybe this is a better UX https://deploy-preview-35202--material-ui.netlify.app/material-ui/api/alert/. I have made sure that searching for "example" yield a result too on the page.

Close #35004

[mui-bot]

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[mnajdova]

👍

[alexfauquette]

One of the ideas we had when discussing the issue was to add an explanation. Hopping it helps people who land on this page discover the structure of the docs. Especially the "Components" section.

Here is the text proposed in the issue:

This API page is a quick reference for the props and classes available to this component. To see demos and details on how to use the component in your app, visit the corresponding page in the Components section of the docs:

[oliviertassinari]

@alexfauquette Ok, I have updated the description.

• I have skipped "This API page is a quick reference for the props and classes available to this component." because it says the same as the description:

• I have shortened it to stay on one line.
• I have replaced "details" with "example" so developers can keyword search on the page.

[samuelsycamore]

Would it make more sense for this section to be a callout? It feels kind of weird to be the first section of the page, but not really a part of the page's flow. I think it should be somewhat eye-catching, since the purpose is to quickly redirect users who've landed on the wrong page.

[oliviertassinari]

Would it make more sense for this section to be a callout?

@samuelsycamore A callout would make the information more likely to be seen by a developer. IMHO, we don't need to go there yet. We already give it more visibility by moving it to the top and the least amount of visibility we can get away with, the better.