Updates `theme.json` to use v2 shape, adds styles to search and file block as well as generic text decoration. Fixes a bug in the layout of a query block pattern.
This is a follow-up to [52081]. These changes are ongoing and development continues on GitHub. To view all of the changes included in this commit, see GitHub: 99db6063be...a11fb4932a
Props desrosj, kjellr, poena.
See #54318.
Built from https://develop.svn.wordpress.org/trunk@52164
git-svn-id: http://core.svn.wordpress.org/trunk@51756 1a063a9b-81f0-0310-95a4-ce76da25c4cd
