* Rename `sr-only`/`sr-only-focusable`
To be more representative of the fact that these are not necessarily "screen reader" specific, but actually apply to assistive technologies in general (and also things like Alexa/Siri/etc). Goes hand-in-hand with #31133
Co-authored-by: XhmikosR <xhmikosr@gmail.com>
- point to WCAG 2.1 rather than 2.0
- soften/expand the language around color contrast, since the situation has definitely improved in v5 but we still can't guarantee all possible permutations of colors/opacities/etc
- minor language/stylistic tweaks
- add further resources
