unify voice waveform format: base64 wf={100chars};dur={ms}; for both desktop and Android

- inputbar.cpp: CSV waveform → base64 log-scale (same as voice_recorder.c)
- messagelist.cpp: sendVoiceMessage removes displayName|dur_sec| prefix, uses wfStr directly
  setVoiceMessageRoles: decodes new format wf={base64};dur={ms};|... from data field
- messagedelegate.cpp: waveform values now pre-normalized 0..1, no log recalculation needed
- VoiceEncoder: no changes needed (was already compatible)

Both platforms now store identical format in chat_msg_submit.data:
  wf=ABCDef...100chars;dur=NNNN;|file_size|block_size|num_blocks|sigs_hex

tools/chatgui/src/messagedelegate.cpp

@@ -710,10 +710,7 @@ void MessageDelegate::paint(QPainter *painter, const QStyleOptionViewItem &optio
             float barW = (float)wfR.width() / wfN;
             int ph = wfR.height() - 3;
             for (int i = 0; i < wfN; i++) {
-                float v = wf[i].toFloat();
-                float db = v > 0.00001f ? 20.0f * log10f(v) : -100.0f;
-                float logV = (db + 60.0f) / 60.0f;
-                if (logV < 0) logV = 0; if (logV > 1) logV = 1;
+                float logV = wf[i].toFloat();  /* already 0..1 normalized */
                 int barH = 2 + (int)(logV * (ph - 2));
                 int x = wfR.left() + (int)(i * barW);
                 int y = wfR.top() + ph - barH;
@@ -724,8 +721,8 @@ void MessageDelegate::paint(QPainter *painter, const QStyleOptionViewItem &optio
                 QColor idle(0x70, 0x70, 0x78, 130);
                 painter->setBrush((isPlaying || isPaused) ? (before ? played : unplayed) : idle);
                 painter->drawRect(QRect(x, y, bw, barH));
-                if (i == 0) GUI_DEBUG("voice paint: wfN=%d wfW=%d v=%.3f dB=%.1f logV=%.2f barH=%d",
-                                      wfN, wfR.width(), v, db, logV, barH);
+                if (i == 0) GUI_DEBUG("voice paint: wfN=%d wfW=%d logV=%.2f barH=%d",
+                                       wfN, wfR.width(), logV, barH);
             }
         }