Study: lesson reminders on by default for new accounts; one-time backfill turns them on for existing accounts; v2.46.0

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

server.js

@@ -44,6 +44,7 @@ import {
   scheduleReengagementEmails,
   scheduleWeeklyDigestEmails,
   backfillCompletedStudies,
+  backfillReminderDefault,
 } from './server/study-helpers.js'
 import { recordVisitor } from './server/routes/analytics.js'
 
@@ -210,6 +211,11 @@ Promise.all([
   .catch(err => {
     console.error('[study] completed-study backfill failed:', err)
   })
+  .then(() => backfillReminderDefault())
+  .then(updated => { if (updated > 0) console.log(`[study] turned lesson reminders on for ${updated} existing accounts`) })
+  .catch(err => {
+    console.error('[study] reminder-default backfill failed:', err)
+  })
   .finally(() => {
     createBackupSnapshot('startup').catch(() => {})
     setInterval(() => {