Add speak and speak-as

[jamesnw]

speak-as is a weird property. What has wide-ish support and any sort of documentation is speak-as inside an @counter-style rule to describe how markers in a list should be read, and that is part of the @counter-style feature.

This feature is NOT that. This feature applies to any element, and confusingly has a different set of valid properties. Should I disambiguate here somehow?

@autonome - I added this to the speech group, but the name of that group is "Web Speech API". Could that group be broadened to include these hints for the speech synthesis? I think just renaming it "Speech" would suffice.

[autonome]

This feature is NOT that. This feature applies to any element, and confusingly has a different set of valid properties. Should I disambiguate here somehow?

If this feature is truly distinct from the speak-as inside a @counter-style, then is worth adding a comment in the yml file. I haven't seen us making this kind of disambiguation inside descriptions, which aim to be standalone.

@autonome - I added this to the speech group, but the name of that group is "Web Speech API". Could that group be broadened to include these hints for the speech synthesis? I think just renaming it "Speech" would suffice.

Sounds good to me. I am all for making groups generally useful as a discovery mechanism, whether for WF contributors or developers generally, and this would achieve that for either audience.

[ddbeck]

A suggestion for the description, to handle the point of confusion you noted. Free to merge with or without the suggestion though.