change notes 2023-08-02

- TODO: User agent checks didn't seem to work in production. - Used `grep -ril "Empty search." _site` to check how I'm indicating such searches to support making the `kbd-hints` dynamic to the presence of results (currently manipulated in `js/kbd-hints.js` and in `js/search/serp.js`) - Added the first [external-results](/search/about#external-results): [ type:external ]