`@mui/icons-material` in-editor preview

Summary 💡

Having a preview of the icons in the editor is similar to having autocomplete available for the API. Our icons explorer is definitely helpful and better if you need inspiration. But if you know what kind of icon you want then in-editor preview should boost productivity.

Examples 🌈

1. link to icons explorer in SvgIcon.d.ts jsdoc
2. This shows a preview (vscode) when hovering over an imported icon

import SvgIcon from '@material-ui/core/SvgIcon';
/**
 * Preview: ![LockIcon](https://fonts.gstatic.com/s/i/materialicons/lock/v4/24px.svg)
 */
declare const LockIcon: typeof SvgIcon;
export default LockIcon;

credit to @leMaik for the markdown idea.

1. Show icon preview in autocomplete (probably requires IDE extension)

Motivation 🔦

Seemed like a useful thing to have to me.

Each of the examples can be explored further and implemented by whomever is looking for some work to do.

[oliviertassinari]

I have never seen an install timeout due to package size. Since these are compressed repetitive content such as this one should have minor impact.

@eps1lon We have had reports about install timeout for this very package in the past: #12432.

[oliviertassinari]

An update on this issue. If we work on it, we would probably need to take 3 constraints into account:

1. Find an icon color that has high contrast for the IDE, skewing for dark mode (as I assume a lot more frequent than light mode)
2. Use PNG instead of SVG, per https://github.com/microsoft/vscode/issues/133389 and #28659
3. Be careful about the icons package bundle size: #12432