Plugins: Consider adding breadcrumbs on Search archives and other internal pages

[ndiego]

This issue was ported over from WordPress Slack.

breadcrumbs: after arriving on the search results page, i wanted to go back to the main plugin directory page. i felt the "plugin directory" link quite hidden and it wasn't clear where that link led to. i think it would be helpful for there to be breadcrumbs. and for the link to either have a back arrow, or to explicitly say "Go back to plugin directory".