Add the new preferred-text-scale env variable

[captainbrosset]

What type of issue is this?

Missing compatibility data

What information was incorrect, unhelpful, or incomplete?

See https://chromestatus.com/feature/5328467685801984
And https://drafts.csswg.org/css-env-1/#text-zoom

The preferred-text-scale CSS environment variable exposes a user's preferred font scale to CSS.
This new CSS env variable is shipping in Chromium 138.

What browsers does this problem apply to, if applicable?

Chromium (Chrome, Edge 79+, Opera, Samsung Internet)

What did you expect to see?

New compat data in https://github.com/mdn/browser-compat-data/blob/main/css/types/env.json

Did you test this? If so, how?

N/A

Can you link to any release notes, bugs, pull requests, or MDN pages related to this?

No response

Do you have anything more you want to share?

No response

MDN URL

No response

MDN metadata

No response

[caugner]

According to https://chromestatus.com/feature/5328467685801984, this only ships in Chrome Android, but neither the implementing commit nor the shipping commit mention this restriction, so it probably ships in Desktop as well.

@captainbrosset Can you confirm?