feat: File attachments (#3031)

* stash

* refactor, working in non-collab + collab editor

* attachment styling

* Avoid crypto require in browser

* AttachmentIcon, handling unknown types

* Do not allow attachment creation for file sizes over limit

* Allow image as file attachment

* Upload placeholder styling

* lint

* Refactor: Do not use placeholder for file attachmentuploads

* Add loading spinner

* fix: Extra paragraphs around attachments on insert

* Bump editor

* fix build error

* Remove attachment placeholder when upload fails

* Remove unused styles

* fix: Attachments on shared pages

* Merge fixes

shared/env.ts

@@ -0,0 +1,5 @@
+import { PublicEnv } from "./types";
+
+const env = typeof window === "undefined" ? process.env : window.env;
+
+export default env as PublicEnv;