Consider moving Metadata_Renderer into Metadata directory

[acicovic]

Is your feature request related to a problem?

Our Metadata_Renderer class (class-metadata-renderer.php) is found under the src/UI directory. Although it contains the word renderer, I wouldn't classify it as a UI element, as its work is to output the metadata into the page's source (thus the "render" part). It doesn't really output anything in the UI like the other classes in the UI directory do.

Describe the solution you'd like

Consider whether the class should be moved into scr/Metadata instead.

Describe alternatives you've considered

Do nothing, things work fine as they are.