- Replace trivial same-word matching pairs (Bag->Bag, Menu->Menu, etc.)
with actual Tagalog vocabulary (Payong->Umbrella, Pagkain->Food, etc.)
- Fix misleading "Match opposite adjectives" prompt to accurately describe
the Tagalog-to-English matching exercise
- Remove awkward slash-separated alternative in directions fill-in-the-blank

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

The phrases lesson had "___ ko." with blank "Hindi ko alam" which
would produce the nonsensical "Hindi ko alam ko." Fixed to
"Hindi ko ___." with blank "alam" for correct "Hindi ko alam."

Also changed let to const for seenSections Set (mutated via .add(),
not reassigned).

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Introduce sections concept (Section 1-4 planned) with section banners
on the home page. Expand Section 1 (Foundations) from 6 to 30 topics
covering CEFR A1 material: greetings, basics, introductions, courtesy,
numbers, colors, family, emotions, adjectives, body parts, clothing,
animals, home, nature, time, days, weather, verbs, daily routine, food,
shopping, market, restaurant, school, jobs, sports, health, directions,
travel, and common phrases.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

The route /api/lesson-state/:topic_id/:lesson_id used the old Axum 0.6
colon syntax which doesn't work in Axum 0.8. Changed to curly brace
syntax so the GET and DELETE endpoints actually match incoming requests.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Add lesson_state table and API endpoints (PUT/GET/DELETE /api/lesson-state)
to persist in-progress lesson state (current exercise index, hearts, correct
count). On lesson load, check for saved state and restore it. After each
exercise advance, save state to the server. On lesson completion, delete the
saved state. This prevents losing all progress on disconnect or page refresh.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Handle browser AudioContext suspension by resuming on use, pass ctx
parameter to playTone to avoid redundant calls, and wrap all play
functions in try/catch for graceful degradation.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Synthesize short tones via Web Audio API - no external audio files needed.
Correct answers play an ascending two-note ding, incorrect answers play a
gentle descending tone, and lesson completion plays a four-note fanfare.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

- Add /api/tts endpoint using msedge-tts crate for high-quality
Filipino neural voices (fil-PH-BlessicaNeural default)
- Disk-based LRU cache in data/tts-cache/ to avoid re-synthesis
- Update useSpeech hook to fetch from server and play audio via
HTMLAudioElement instead of Web Speech API
- Add loading spinner to SpeakButton while audio is fetched
- TTS is now always available regardless of browser support

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

- Remove orphaned Divider in ReviewPage card (no content above it after
message moved to SpeechBubble)
- Remove unused Divider import
- Simplify lowHeartMessages in LessonPage: only 2 of 4 entries were
reachable, replaced array with direct ternary

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

- Add 'encourage' mood with nodding animation
- Create SpeechBubble component for Rambi to "speak"
- Add Rambi to correct/incorrect feedback banners with Tagalog phrases
- Enhance ReviewPage with speech bubble and varied score-based messages
- Show Rambi encouragement during lessons when hearts are low

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Rename the mascot component from Rambutan to Rambi and introduce the
name in the HomePage greeting ("Kamusta! I'm Rambi!"). Update all
imports across LoginPage, RegisterPage, and ReviewPage.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

vite-plugin-pwa@1.2.0 only supports vite up to v7, causing npm ci
to fail in the Docker build. Setting legacy-peer-deps=true allows
the install to proceed while the upstream adds vite@8 support.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Replace the lightning bolt favicon with a rambutan mascot SVG matching
the in-app character. Set the tab title to "Ayos". Add PWA support via
vite-plugin-pwa with manifest, service worker, and installability in
Chrome. Generate PNG icons at 192x192, 512x512, and 180x180 for
apple-touch-icon. Include cargo fmt formatting fixes.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>