chore: catch up Storybook preview, coverage, and story hygiene

Stories were throwing without AuthModal/CreateFlow providers, autodocs was a no-op, and several DS/create-flow screens had no stories.

stories/pages/UploadPage.stories.js

@@ -1,7 +1,7 @@
 import { CommunityUploadScreen } from "../../app/(app)/create/screens/upload/CommunityUploadScreen";
 
 export default {
-  title: "Pages/Create/CommunityUpload",
+  title: "Pages/Create Flow/Community upload",
   component: CommunityUploadScreen,
   parameters: { layout: "fullscreen" },
 };