feat: waveform display + 3px progress bar in bubble + sliding window RMS

- AudioRecorder: sliding window RMS (avg 5 frames), waveformLevels() getter
- InputBar: downsample RMS to 100 samples, encode as wf0,wf1,... in textData
- MessageList: parse 3rd pipe-separated field as waveform, store in MsgVoiceWaveformRole
- MessageDelegate: new voice layout (16px play btn + 25px waveform + 3px progress bar)
- MessageDelegate: waveform bars colored by progress (blue before, gray after)
- Progress bar integrated at bottom of waveform area as colored fill

tools/chatgui/src/audiorecorder.cpp

@@ -26,7 +26,17 @@ void audioCaptureCallback(ma_device* pDevice, void* pOutput, const void* pInput,
         float v = (float)src[i] / 32768.0f;
         sumSq += v * v;
     }
-    self->m_peakLevel = sqrtf(sumSq / (float)(frameCount * self->m_channels));
+    float rms = sqrtf(sumSq / (float)(frameCount * self->m_channels));
+    self->m_peakLevel = rms;
+
+    self->m_recentRms[self->m_rmsIdx % 5] = rms;
+    self->m_rmsIdx++;
+    if (self->m_rmsIdx >= 5) {
+        float avg = 0.0f;
+        for (int i = 0; i < 5; i++) avg += self->m_recentRms[i];
+        avg /= 5.0f;
+        self->m_waveformLevels.push_back(avg);
+    }
 }
 
 AudioRecorder::AudioRecorder(QObject* parent)
@@ -72,6 +82,8 @@ void AudioRecorder::startRecording() {
     if (!m_initialized) { qWarning("AudioRecorder: not initialized"); return; }
 
     m_pcmBuffer.clear();
+    m_waveformLevels.clear();
+    m_rmsIdx = 0;
     m_elapsedMs = 0;
 
     ma_context* ctx = SoundManager::instance()->context();