Phase 2: learning engine — history, SRS review, mistakes, stats, exam, reminders

Answer history and schedules
- Every answer is recorded (deck, activity, topic, correct/wrong, time)
  in a versioned IndexedDB log (freezmo-learning v1, stores answers +
  srs), mirrored in memory for synchronous React reads and capped at
  20k answers (oldest pruned). StudyFeed records as it grades.
- Light SM-2 schedule per activity: 1 day, 3 days, then interval x
  ease; wrong answers return in ten minutes with the ease nudged down.

Review, mistakes, stats
- Library 'Smart review' card: due count, mistakes count (latest
  answer wrong — clears itself when answered correctly), today's goal
  progress. Review sessions freeze their item list at start.
- New /review (due across decks, ?mistakes=1 global or ?deck= per
  deck) built on a shared SessionFeed with the study feed's snap/keyboard
  mechanics, wake lock and a results slide.
- New /stats: day streak, five-week calendar, accuracy per subject and
  per deck, weakest topics (>=3 answers), daily-goal progress.
- Daily goal configurable in Settings (10/20/30/50).

Exam mode
- New /exam: pick decks, question count, optional timer; no hints
  (a NoHints context hides hint rows and the self-check escape);
  results with score, per-deck and per-topic breakdown; wrong answers
  land in the mistakes set through the normal history.

Reminders (conditional)
- VAPID-gated: GET/POST/DELETE /api/push and POST /api/push/test with
  the standard route pattern, RATE_LIMIT_PUSH, zod, auth before body.
  Subscriptions stored server-side as endpoint + keys only (PUSH_DIR).
  UI hidden entirely without keys; iOS install note; service worker
  push/notificationclick handlers; scripts/send-reminders.mjs for a
  cron/systemd timer; web-push added as the one server dependency.

Verified: new phase-2 suite 42/42 (history/SRS shapes from a real study
run, mistakes clearing, review session, stats math, exam timer and
breakdowns, VAPID-less hidden state plus the configured
subscribe/validate/test/delete path against a second instance) plus
regression 74/74, mobile 52/52, wizard 80/80, declutter 116/116,
animation 8/8, native 35/35, phase1 38/38, i18n 25/25. Key parity
709/709. Lint + build clean. SW freezmo-v26.

components/SettingsDialog.tsx

@@ -9,6 +9,7 @@ import { modelErrorCopy } from "@/lib/model-errors";
 import { springSheet } from "@/lib/motion";
 import { ModelErrorActions } from "@/components/ModelErrorActions";
 import { DataSection } from "@/components/DataSection";
+import { LearningSection } from "@/components/LearningSection";
 import { SyncSection } from "@/components/SyncSection";
 import { clearApiKey, saveSettings, settingsStore } from "@/lib/settings";
 import { useBackClose } from "@/lib/use-back-close";
@@ -393,6 +394,7 @@ export function SettingsDialog({
                     </section>
 
                     {/* ------------------------------------------- data & sync */}
+                    <LearningSection />
                     <DataSection />
                     <SyncSection />
 
@@ -708,6 +710,7 @@ export function SettingsDialog({
                 </section>
 
                 {/* ------------------------------------------- data & sync */}
+                <LearningSection />
                 <DataSection />
                 <SyncSection />