As discussed in #4773 there was not any clarification as why auth button sizes were reduced so 36px is now accepted as default. This commit addresses that comment/issue.
- Add preferred provider for authorization to login and signup pages.
To use, the 3rd party application would have to add `preferred_provider=...`
parameter to OAuth2 authorization request.
- Resize 3rd party provider icons
- Add "login to authorize" heading to login and signup screens
This makes future refactoring easier, since the elements will
retain their borders even if the hierarchy changes.
Also round some maps and the legale section since I think those now
look nicer.
This prevents reflow when the images are loaded by the browser.
ActiveStorage variants are resized lazily when the image is requested,
so we only know the dimensions if the image was already loaded. This
means that there will be one reflow just after a new avatar is first
viewed.
