New login screen (#1331)

* wip

* feat: first draft of auth.config

* chore: auth methodS

* chore: styling

* styling, styling, styling

* feat: Auth notices

* chore: Remove server-rendered pages, move shared/components -> components

* lint

* cleanup

* cleanup

* fix: Remove unused component

* fix: Ensure env variables in prod too

* style tweaks

* fix: Entering SSO email into login form fails
fix: Tweak language around guest signin

package.json

@@ -155,7 +155,6 @@
     "string-replace-to-array": "^1.0.3",
     "styled-components": "^5.0.0",
     "styled-components-breakpoint": "^2.1.1",
-    "styled-components-grid": "^2.2.1",
     "styled-normalize": "^8.0.4",
     "tiny-cookie": "^2.3.1",
     "tmp": "0.0.33",