Remove duplicates in the web interface

The settings page has one Save button helper. The story list sorts by
the sort key that the server sends, so the rule for a leading article
exists once. The story page takes its list of download modes from the
mode hints.

tests/js/story-list.test.mjs

@@ -16,8 +16,11 @@ const { storiesPage } = await import('../../bindery/static/js/stories.js');
 const { refreshJobs, startPolling, stopPolling } = await import('../../bindery/static/js/jobs.js');
 const { fmtDate } = await import('../../bindery/static/js/lib.js');
 
+// The server gives each story its sort key: the title in lower case, without a leading article.
 const story = (id, title, changes = {}) => ({
-  id, title, url: `https://example.com/${id}`, author: 'Reader', site: 'example.com',
+  id, title, url: `https://example.com/${id}`,
+  sort_title: (title || `https://example.com/${id}`).trim().replace(/^(?:the|an?)\s+/i, '').toLowerCase(),
+  author: 'Reader', site: 'example.com',
   chapter_count: 42, offsite_count: 0, revised_count: 0, status: 'ok', message: 'No changes',
   last_changed: null, last_checked: null, ...changes,
 });

tests/js/upload-hold.test.mjs

@@ -330,11 +330,11 @@ test('approval before a build still shows the pause and never offers to send', a
 test('the story list marks only an approval hold, not every unsent book', async (t) => {
   const backend = server(t);
   backend.on('GET', 'stories', [
-    { id: 1, url: 'u1', title: 'Held', author: 'A', site: 's', chapter_count: 1, offsite_count: 0, status: 'ok',
+    { id: 1, url: 'u1', title: 'Held', sort_title: 'held', author: 'A', site: 's', chapter_count: 1, offsite_count: 0, status: 'ok',
       message: '', upload_held: true, approval_held: true },
-    { id: 2, url: 'u2', title: 'Sent', author: 'A', site: 's', chapter_count: 1, offsite_count: 0, status: 'ok',
+    { id: 2, url: 'u2', title: 'Sent', sort_title: 'sent', author: 'A', site: 's', chapter_count: 1, offsite_count: 0, status: 'ok',
       message: '', upload_held: false, approval_held: false },
-    { id: 3, url: 'u3', title: 'Paused', author: 'A', site: 's', chapter_count: 1, offsite_count: 0, status: 'ok',
+    { id: 3, url: 'u3', title: 'Paused', sort_title: 'paused', author: 'A', site: 's', chapter_count: 1, offsite_count: 0, status: 'ok',
       message: '', upload_held: true, approval_held: false },
   ]);
   backend.on('GET', 'jobs', []);

tests/test_store.py

@@ -55,6 +55,8 @@ def test_list_stories_sorts_titles_without_leading_articles(tmp_path):
         store.create_story(f"https://example/s/{n}", "example", title, "A", [])
     titles = [s["title"] for s in store.list_stories()]
     assert titles == ["Anthem", "A Bee", "Cat", "an Owl", "Theory", "The Zebra"]
+    # The web interface sorts by the same key.
+    assert [s["sort_title"] for s in store.list_stories()] == ["anthem", "bee", "cat", "owl", "theory", "zebra"]
 
 
 def test_cover_replaces_previous_cover(tmp_path):