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>

server/index.js

@@ -11,6 +11,7 @@ import { startReminderScheduler } from './reminders.js';
 import { startBackupScheduler } from './backups.js';
 import { registerBibleRoutes } from './bibleApi.js';
 import { registerIqBibleRoutes } from './iqbible.js';
+import { registerStrongsRoutes } from './strongs.js';
 import { registerDeviceRoutes } from './devices.js';
 import { requireAuth } from './auth.js';
 import { userPayload } from './userPayload.js';
@@ -85,6 +86,7 @@ registerProjectRoutes(app);
 registerReaderRoutes(app);
 registerBibleRoutes(app, requireAuth);
 registerIqBibleRoutes(app, requireAuth);
+registerStrongsRoutes(app, requireAuth);
 registerDeviceRoutes(app, { requireAuth, userPayload, isLimited, recordFailure, clearFailures, tooMany: TOO_MANY });
 registerSharingRoutes(app);
 registerAdminRoutes(app);