Teaching tools: word occurrences, blanks handout, templates, series progress, book info, comments

- Words tab: "Where else" lists every verse using a Strong's number, by book
  (new /api/strongs/:number/occurrences, indexed from the interlinear files)
- Handout: fill-in-the-blanks layout with a word bank
- Four new study templates: character, topical, word, verse by verse
- Finish: series progress (not started / studied / ready / taught)
- Background: book at a glance for all 66 books
- Chunk comments for co-teachers, merged between copies
- TODO: correct BSB audio note, tick co-teacher comments

Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>

src/utils/seriesProgress.test.js

@@ -0,0 +1,38 @@
+import { test, expect } from 'vitest';
+import { seriesProgress, stageOf } from './seriesProgress.js';
+
+const chunk = (id, x = {}) => ({ id, startVerse: 1, endVerse: 2, ...x });
+const project = (chunks, outline = []) => ({ title: 'Romans', outline, chapters: [{ book: 'Romans', bookAbbrev: 'ROM', chapter: '8', verses: [], chunks }] });
+
+test('a session moves from not started to taught as things get written', () => {
+  const p = project([chunk('a')]);
+  expect(stageOf(p, chunk('a'))).toBe(0);
+  expect(stageOf(p, chunk('a', { observation: 'Notes' }))).toBe(1);
+  expect(stageOf(p, chunk('a', { observation: 'Notes', discussionQuestions: 'Why?' }))).toBe(2);
+  expect(stageOf(p, chunk('a', { observation: 'Notes', groupNotes: 'They liked it' }))).toBe(3);
+  expect(stageOf(p, chunk('a', { attendees: '   ' }))).toBe(0);
+});
+
+test('an outline point linked to the session counts as ready to teach', () => {
+  const p = project([chunk('a', { application: 'x' })], [{ id: 'o', text: 'Point', chunkId: 'a', children: [] }]);
+  expect(stageOf(p, p.chapters[0].chunks[0])).toBe(2);
+});
+
+test('the series summary counts stages, open follow-ups and comments, and names the next session to teach', () => {
+  const p = project([
+    chunk('a', { groupNotes: 'Done', followUps: [{ id: 'f1', text: 'x', done: false }, { id: 'f2', text: 'y', done: true }] }),
+    chunk('b', { observation: 'Started', comments: [{ id: 'c1', done: false }, { id: 'c2', done: true }] }),
+    chunk('c'),
+  ]);
+  const s = seriesProgress(p);
+  expect(s.counts).toEqual([1, 1, 0, 1]);
+  expect(s.taught).toBe(1);
+  expect(s.total).toBe(3);
+  expect(s.rows[0].openFollowUps).toBe(1);
+  expect(s.rows[1].openComments).toBe(1);
+  expect(s.next.id).toBe('b');
+});
+
+test('a finished series has no next session', () => {
+  expect(seriesProgress(project([chunk('a', { teachBack: 'x' })])).next).toBeNull();
+});