feat: echte Pair-Audios statt TTS, Klick auf Satz spielt Audio (preloaded)

- usePairAudio-Hook: preload beim Kachel-Mount, nur eine Stimme gleichzeitig
- PairSentenceCard: audio_url statt speechSynthesis (TTS nur noch Fallback)
- PairYesNoCard/PairWordCard: Frage klickbar + Speaker-Button (vorher kein Audio)

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

src/components/PairCards.css

@@ -215,6 +215,12 @@
   flex: 1;
 }
 
+/* Clickable sentence — tap to play audio */
+.pair-sentence-clickable {
+  cursor: pointer;
+  user-select: none;
+}
+
 /* Word chips inside sentences — underline italic style */
 .pair-word-chip {
   display: inline;

src/components/PairSentenceCard.jsx

@@ -1,5 +1,6 @@
 import { useState, useRef } from 'react'
 import confetti from 'canvas-confetti'
+import usePairAudio from '../hooks/usePairAudio'
 import './PairCards.css'
 
 function triggerConfetti() {
@@ -112,6 +113,8 @@ export default function PairSentenceCard({ card, onComplete }) {
   const hint     = stmt?.[`sentence_${native}`] || null
   const pic      = card.picture?.url
 
+  const { play, playing } = usePairAudio(stmt?.audio_url)
+
   const isWord   = activeChip && activeChip.type === 'word'
   const isObject = activeChip && activeChip.type === 'object' && activeChip.selections?.length
 
@@ -129,7 +132,9 @@ export default function PairSentenceCard({ card, onComplete }) {
     setTimeout(() => onComplete('correct'), 900)
   }
 
-  function handleTTS() {
+  function handlePlay() {
+    if (play()) { setUnlocked(true); return }
+    // Fallback: Browser-TTS, falls kein Audio-File vorhanden
     if (!window.speechSynthesis || !sentence) return
     window.speechSynthesis.cancel()
     const utt = new SpeechSynthesisUtterance(toPlainText(sentence))
@@ -178,7 +183,8 @@ export default function PairSentenceCard({ card, onComplete }) {
 
         <div className="pair-sentence-row">
           <div className="pair-sentence-text">
-            <p className="pair-sentence" style={{ opacity: showTranslation ? 0 : 1, transition: 'opacity 0.18s', margin: 0 }}>
+            <p className="pair-sentence pair-sentence-clickable" onClick={handlePlay}
+              style={{ opacity: showTranslation ? 0 : 1, transition: 'opacity 0.18s', margin: 0 }}>
               {resolveSentence(sentence, card.placeholders, handleChipClick, activeChip?.id)}
             </p>
             {hint && (
@@ -196,8 +202,8 @@ export default function PairSentenceCard({ card, onComplete }) {
           </div>
 
           <div style={{ display: 'flex', flexDirection: 'column', gap: 8, paddingTop: 2 }}>
-            {/* TTS — playing unlocks "Verstanden" */}
+            {/* Vorlesen — playing unlocks "Verstanden" */}
-            <button className={`pair-icon-btn${unlocked ? ' active' : ''}`} onClick={handleTTS} title="Vorlesen">
+            <button className={`pair-icon-btn${unlocked || playing ? ' active' : ''}`} onClick={handlePlay} title="Vorlesen">
               <svg width="18" height="18" viewBox="0 0 24 24" fill="none" stroke="currentColor" strokeWidth="1.8" strokeLinecap="round" strokeLinejoin="round">
                 <polygon points="11 5 6 9 2 9 2 15 6 15 11 19 11 5"/>
                 <path d="M15.54 8.46a5 5 0 0 1 0 7.07"/>

src/components/PairWordCard.jsx

@@ -1,5 +1,6 @@
 import { useState, useMemo } from 'react'
 import confetti from 'canvas-confetti'
+import usePairAudio from '../hooks/usePairAudio'
 import './PairCards.css'
 
 function triggerConfetti() {
@@ -103,6 +104,8 @@ export default function PairWordCard({ card, onComplete }) {
   const hint     = q?.[`sentence_${native}`] || null
   const pic      = card.picture?.url
 
+  const { play, playing } = usePairAudio(q?.audio_url)
+
   const options = useMemo(() => {
     const pos  = (stmt?.positive_words || []).map(w => ({ ...w, correct: true }))
     const neg2 = (neg?.negative_words  || []).map(w => ({ ...w, correct: false }))
@@ -155,7 +158,9 @@ export default function PairWordCard({ card, onComplete }) {
 
       <div className="pair-card-body" onClick={e => e.stopPropagation()} style={{ paddingTop: 18 }}>
 
-        <p className="pair-question">
+        <div className="pair-sentence-row">
+          <div className="pair-sentence-text">
+            <p className="pair-question pair-sentence-clickable" onClick={() => play()}>
               {resolveSentence(sentence, card.placeholders, handleChipClick, activeChip?.id)}
             </p>
             {hint && !confirmed && (
@@ -163,6 +168,15 @@ export default function PairWordCard({ card, onComplete }) {
                 {resolveSentence(hint, card.placeholders, null, null)}
               </p>
             )}
+          </div>
+          <button className={`pair-icon-btn${playing ? ' active' : ''}`} onClick={() => play()} title="Vorlesen">
+            <svg width="18" height="18" viewBox="0 0 24 24" fill="none" stroke="currentColor" strokeWidth="1.8" strokeLinecap="round" strokeLinejoin="round">
+              <polygon points="11 5 6 9 2 9 2 15 6 15 11 19 11 5"/>
+              <path d="M15.54 8.46a5 5 0 0 1 0 7.07"/>
+              <path d="M19.07 4.93a10 10 0 0 1 0 14.14"/>
+            </svg>
+          </button>
+        </div>
 
         <div className="pair-options">
           {options.map((opt) => {

src/components/PairYesNoCard.jsx

@@ -1,5 +1,6 @@
 import { useState } from 'react'
 import confetti from 'canvas-confetti'
+import usePairAudio from '../hooks/usePairAudio'
 import './PairCards.css'
 
 function triggerConfetti() {
@@ -91,6 +92,8 @@ export default function PairYesNoCard({ card, onComplete }) {
   const sentence = q?.[`sentence_${lang}`] || q?.sentence_de
   const hint     = q?.[`sentence_${native}`] || null
 
+  const { play, playing } = usePairAudio(q?.audio_url)
+
   function handleChipClick(id, entry) {
     setActiveChip(prev => prev?.id === id ? null : { id, ...entry })
   }
@@ -126,7 +129,9 @@ export default function PairYesNoCard({ card, onComplete }) {
 
       <div className="pair-card-body" onClick={e => e.stopPropagation()} style={{ paddingTop: 18 }}>
 
-        <p className="pair-question">
+        <div className="pair-sentence-row">
+          <div className="pair-sentence-text">
+            <p className="pair-question pair-sentence-clickable" onClick={() => play()}>
               {resolveSentence(sentence, card.placeholders, handleChipClick, activeChip?.id)}
             </p>
             {hint && !result && (
@@ -134,6 +139,15 @@ export default function PairYesNoCard({ card, onComplete }) {
                 {resolveSentence(hint, card.placeholders, null, null)}
               </p>
             )}
+          </div>
+          <button className={`pair-icon-btn${playing ? ' active' : ''}`} onClick={() => play()} title="Vorlesen">
+            <svg width="18" height="18" viewBox="0 0 24 24" fill="none" stroke="currentColor" strokeWidth="1.8" strokeLinecap="round" strokeLinejoin="round">
+              <polygon points="11 5 6 9 2 9 2 15 6 15 11 19 11 5"/>
+              <path d="M15.54 8.46a5 5 0 0 1 0 7.07"/>
+              <path d="M19.07 4.93a10 10 0 0 1 0 14.14"/>
+            </svg>
+          </button>
+        </div>
 
         {result && (
           <p className={`pair-feedback ${result}`}>

src/hooks/usePairAudio.js

@@ -0,0 +1,42 @@
+import { useEffect, useRef, useState } from 'react'
+
+// Nur eine Stimme gleichzeitig im Feed
+let currentAudio = null
+
+export default function usePairAudio(url) {
+  const audioRef = useRef(null)
+  const [playing, setPlaying] = useState(false)
+
+  useEffect(() => {
+    if (!url) { audioRef.current = null; return }
+    const audio = new Audio(url)
+    audio.preload = 'auto'
+    const onPlay  = () => setPlaying(true)
+    const onStop  = () => setPlaying(false)
+    audio.addEventListener('play', onPlay)
+    audio.addEventListener('pause', onStop)
+    audio.addEventListener('ended', onStop)
+    audioRef.current = audio
+    return () => {
+      audio.pause()
+      audio.removeEventListener('play', onPlay)
+      audio.removeEventListener('pause', onStop)
+      audio.removeEventListener('ended', onStop)
+      if (currentAudio === audio) currentAudio = null
+      audio.src = ''
+      audioRef.current = null
+    }
+  }, [url])
+
+  function play() {
+    const audio = audioRef.current
+    if (!audio) return false
+    if (currentAudio && currentAudio !== audio) currentAudio.pause()
+    currentAudio = audio
+    audio.currentTime = 0
+    audio.play().catch(() => {})
+    return true
+  }
+
+  return { play, playing }
+}