Simplify the upload state and the story page data

The pause of the user and a missing ingest folder are separate checks.
One function gives the upload state to the settings and the story page.
A route that returns only a story no longer loads its chapters or asks
CWA for its book. The story page data loses the values that no page reads.

tests/js/flows.test.mjs

@@ -647,7 +647,7 @@ test('with CWA off, the pages show nothing about CWA', async () => {
   assert.ok(section(main, 'Library link'));
   const off = { ...config, cwa_enabled: false, library_available: false };
   // Values that show a notice with CWA on.
-  Object.assign(details, { uploads_paused: true, ingest_available: false, link_books: false });
+  Object.assign(details, { pause_uploads: true, ingest_available: false, link_books: false });
   details.story.upload_held = true;
   await mountStory(off);
   assert.ok(section(main, 'Metadata'));