Mirroring icons (and emojis)

[xfq]

There should be some content in alreq about what kind of "directional" icons (and emojis) should be flipped and what should not be flipped in RTL text, at least some general guidelines and examples.

Some related information:

• https://m2.material.io/design/usability/bidirectionality.html#mirroring-layout
• https://rtlstyling.com/posts/rtl-styling#bidirectional-icons
• https://github.com/shervinafshar/Persian-HIG/blob/main/en/PersianHIG_EN_Main4_TOC.md