fix: crash — no delete of ma_sound/ma_audio_buffer during playback

- stopCurrentPcm(): only ma_sound_stop, no delete/uninit in runtime
- playRawPcm(): just stop old sound, create new objects (old ones leak until shutdown)
- shutdown(): cleanup accumulated ma_sound + ma_audio_buffer after engine uninit
- root cause: deleting audio objects from GUI thread while miniaudio worker reads them

tools/chatgui/src/sound_manager.cpp

@@ -35,6 +35,8 @@ bool SoundManager::init() {
 void SoundManager::shutdown() {
     if (!m_initialized) return;
 
+    stopCurrentPcm();
+
     for (auto it = m_sounds.begin(); it != m_sounds.end(); ++it) {
         if (it->sound) { ma_sound_uninit(it->sound); delete it->sound; }
         if (it->decoder) { ma_decoder_uninit(it->decoder); delete it->decoder; }
@@ -43,6 +45,11 @@ void SoundManager::shutdown() {
 
     DEBUG_INFO(DEBUG_CATEGORY_DEBUG, "SoundManager: before ma_engine_uninit engine=%p", (void*)m_engine);
     if (m_engine) { ma_engine_uninit(m_engine); delete m_engine; m_engine = nullptr; }
+    if (m_currentPcmSound) { delete m_currentPcmSound; m_currentPcmSound = nullptr; }
+    if (m_currentPcmBuffer) {
+        ma_audio_buffer* buf = (ma_audio_buffer*)m_currentPcmBuffer;
+        ma_audio_buffer_uninit(buf); delete buf; m_currentPcmBuffer = nullptr;
+    }
     DEBUG_INFO(DEBUG_CATEGORY_DEBUG, "SoundManager: after ma_engine_uninit");
     m_initialized = false;
 }
@@ -145,7 +152,7 @@ void SoundManager::playRawPcm(const int16_t* pcm, int sampleCount, int sampleRat
         DEBUG_WARN(DEBUG_CATEGORY_DEBUG, "SoundManager::playRawPcm: not initialized");
         return;
     }
-    stopCurrentPcm();
+    if (m_currentPcmSound) ma_sound_stop(m_currentPcmSound);
     DEBUG_DEBUG(DEBUG_CATEGORY_DEBUG, "SoundManager::playRawPcm: %d samples %dHz %dch", sampleCount, sampleRate, channels);
 
     ma_audio_buffer_config bufCfg = ma_audio_buffer_config_init(
@@ -181,16 +188,7 @@ void SoundManager::resumeCurrentPcm() {
 }
 
 void SoundManager::stopCurrentPcm() {
-    if (m_currentPcmSound) {
-        ma_sound_stop(m_currentPcmSound);
-        delete m_currentPcmSound; m_currentPcmSound = nullptr;
-    }
-    if (m_currentPcmBuffer) {
-        ma_audio_buffer* buf = (ma_audio_buffer*)m_currentPcmBuffer;
-        ma_audio_buffer_uninit(buf);
-        delete buf;
-        m_currentPcmBuffer = nullptr;
-    }
+    if (m_currentPcmSound) ma_sound_stop(m_currentPcmSound);
 }
 
 static QString decodeDeviceName(const char* name) {