feat(tts): multi-voice switcher for EN & RU, Irina default voice, punctuation pause normalization and speed calibration

app/static/js/modules/api.js

@@ -185,8 +185,12 @@ export const api = {
 
     // Listening Comprehension Trainer
     listening: {
-        async getExercise(topic = 'all', level = 'B1') {
-            const resp = await fetch(`/api/listening/exercise?topic=${encodeURIComponent(topic)}&level=${encodeURIComponent(level)}`);
+        async getExercise(topic = 'all', level = 'B1', voice = null) {
+            let url = `/api/listening/exercise?topic=${encodeURIComponent(topic)}&level=${encodeURIComponent(level)}`;
+            if (voice) {
+                url += `&voice=${encodeURIComponent(voice)}`;
+            }
+            const resp = await fetch(url);
             if (resp.ok) return await resp.json();
             throw new Error(`Failed to load listening exercise: ${resp.status}`);
         },
@@ -206,6 +210,14 @@ export const api = {
         }
     },
 
+    // Neural Speech Synthesis (TTS)
+    tts: {
+        async getStatus() {
+            const resp = await fetch('/api/tts/status');
+            return resp.ok ? await resp.json() : null;
+        }
+    },
+
     // Bookshelf & Reader
     books: {
         async getAll() {

app/static/js/modules/srs.js

@@ -111,6 +111,7 @@ export function initSrs() {
     const listeningLevelBadge = document.getElementById('listening-level-badge');
     const listeningTopicBadge = document.getElementById('listening-topic-badge');
     const listeningTopicSelect = document.getElementById('listening-topic-select');
+    const listeningVoiceSelect = document.getElementById('listening-voice-select');
     const listeningSpeedSelect = document.getElementById('listening-speed-select');
     const listeningNewScenarioBtn = document.getElementById('listening-new-scenario-btn');
     const listeningTitle = document.getElementById('listening-title');
@@ -715,8 +716,9 @@ export function initSrs() {
         if (listeningTitle) listeningTitle.textContent = 'Загрузка аудио-ситуации...';
 
         const topic = listeningTopicSelect ? listeningTopicSelect.value : 'all';
+        const voice = listeningVoiceSelect ? listeningVoiceSelect.value : (localStorage.getItem('notes_tts_voice_en') || 'en_US-lessac');
         try {
-            const data = await api.listening.getExercise(topic, 'B1');
+            const data = await api.listening.getExercise(topic, 'B1', voice);
             currentListeningExercise = data;
 
             if (listeningTitle) listeningTitle.textContent = data.title || 'Ситуация для аудирования';
@@ -788,6 +790,14 @@ export function initSrs() {
         });
     }
 
+    if (listeningVoiceSelect) {
+        listeningVoiceSelect.value = localStorage.getItem('notes_tts_voice_en') || 'en_US-lessac';
+        listeningVoiceSelect.addEventListener('change', () => {
+            localStorage.setItem('notes_tts_voice_en', listeningVoiceSelect.value);
+            loadListeningExercise(true);
+        });
+    }
+
     if (listeningForm) {
         listeningForm.addEventListener('submit', async (e) => {
             e.preventDefault();

app/static/js/modules/ui.js

@@ -194,8 +194,14 @@ export function playAudio(url, speed = 1.0) {
     }
 }
 
-export function playTextSpeech(text, lang = 'en', speed = 1.0) {
+export function playTextSpeech(text, lang = 'en', speed = 1.0, voice = null) {
     if (!text || !text.trim()) return null;
-    const url = `/api/tts?text=${encodeURIComponent(text.trim())}&lang=${lang}&speed=${speed}`;
+    const isRu = lang && lang.toLowerCase().startsWith('ru');
+    const savedVoice = isRu ? localStorage.getItem('notes_tts_voice_ru') : localStorage.getItem('notes_tts_voice_en');
+    const activeVoice = voice || savedVoice;
+    let url = `/api/tts?text=${encodeURIComponent(text.trim())}&lang=${lang}&speed=${speed}`;
+    if (activeVoice) {
+        url += `&voice=${encodeURIComponent(activeVoice)}`;
+    }
     return playAudio(url, speed);
 }