docs: convert list/pag/progb/progs/rad/rip/elev to signals

[msmallest]

Description

Converts the following components to use signals

Part of an effort to address this issue about compatibility with new defaults: #33443

• List
• Paginator
• Progress Bar
• Progress Spinner
• Radio Button
• Ripple (core) example
• Elevation (see note)

Ripple and Elevation are considered "Core" items, but have no "Examples" section in the "Core" page. However, Ripples are in the docs Components sidenav and the "Examples" tab houses the example that was updated.

And I also converted a (core) elevation example. Unlike Ripple which was a "Components" sidenav item whose example is nested under the /core folder of the component examples, I could not find usage of Elevation in practice in the docs. So I was not able to smoketest it, but it should be legit as I double checked it when reviewing my code first.

PR scope

I thought that 7 components worth of changes was a good chunk. There is more chunks to come for other components.

This time around I only made this one branch, since the last PR as one chunk worked well: #33492. Thank you.

Extras

For personal reference, here is my checklist of doc examples worked through: https://gist.github.com/msmallest/f77adb004b9e88c49b3a248bab90a26a?permalink_comment_id=6237101#gistcomment-6237101

[crisbeto]

This PR was merged into the repository. The changes were merged into the following branches:

• main: 8205e24
• 22.0.x: 7535cbe