Theme & page content should be translated

[ryelle]

The page content from patterns is correctly translated, but there are places where the content comes from the WP database that aren't translated.

For example, viewing Astra, which has da translations— on the old site, the description and theme tags appear translated, but on the new theme, they're in English. The title could also be translated (see Hello Elementor),

Old theme	New theme

There are other untranslated strings, but those are not available to GlotPress yet.

[ryelle]

The translated content/title are handled by the Themes_API class, so hooking in to replace those should work.

For the theme tags & page titles, we'll probably want to do something like https://github.com/WordPress/pattern-directory/pull/275