Those were all low hanging fruits - all were already glimmer components, so this was mostly merging js and hbs files and adding imports.
(occasionally also adds/fixes class names)
When we "pull hotlinked images" on onebox images, they are added to the uploads table and their dominant color is calculated. This commit adds the data to the HTML so that it can be used by the client in the same way as non-onebox images. It also adds specific handling to the new `discourse-lazy-videos` plugin.
