call: P2P аудиозвонки — сигналинг, релей медиа, аудио-контур, headless/desktop/android

- src/call/: сигналинг (call.c, call_proto.h, ETCP_RT_ID_CALL 0x36) + релей медиа
  + headless аудио-сокет (call_headless.c, call_audio_bind) + Opus/jitter/тоны
- chat: события CHAT_EVT_CALL_* (34–40), CHAT_EVT_DM_MESSAGES (41), DM-трамплины
- chatgui: call window, miniaudio I/O, audio_frame_ring, test_audio_jitter
- chatgui-android: CallScreen/IncomingCallDialog, аудио-роутинг, JNI, рингтон
- tests: test_call, test_call_headless

tools/chatgui/db/db_manager.cpp

@@ -302,6 +302,29 @@ MessageRow DbManager::getMessageById(const QString& chId, qint64 msgId) const {
     return m;
 }
 
+/* ── DM-беседы (UI, read-only) ── */
+
+QList<DmConversation> DbManager::getDmConversations() const {
+    QList<DmConversation> list;
+    if (!m_db) return list;
+    sqlite3_stmt* stmt = prepareOrNull(
+        "SELECT conv_id, peer_node_id, COALESCE(peer_name,''), last_ts, last_out_seq, last_in_seq"
+        " FROM dm_conversations ORDER BY last_ts DESC");
+    if (!stmt) return list;
+    while (sqlite3_step(stmt) == SQLITE_ROW) {
+        DmConversation c;
+        c.convId     = colText(stmt, 0);
+        c.peerNodeId = (quint64)sqlite3_column_int64(stmt, 1);
+        c.peerName   = colText(stmt, 2);
+        c.lastTs     = sqlite3_column_int64(stmt, 3);
+        c.lastOutSeq = sqlite3_column_int64(stmt, 4);
+        c.lastInSeq  = sqlite3_column_int64(stmt, 5);
+        list.append(c);
+    }
+    sqlite3_finalize(stmt);
+    return list;
+}
+
 /* ── peers (UI) ── */
 
 QMap<quint64, QString> DbManager::getLocalNicknames(const QString& chId) const {