android: member list screen + link status dots, ipv6 autoconnect fixes

Android chatgui:
- New MemberListScreen with member list, detail card, edit dialog
- Link status dots (green/red/grey) per address in detail card (1s poll)
- Self-node name coloured green
- ChatScreen: people icon in TopAppBar

IPv6 autoconnect fixes (3 bugs in conn_mgr/topo):
- topo_node_sqlite_node_load: load v6 addresses from DB
- topo_node_registry_store: merge v6_addrs into existing node
- cm_sock_v6_classify: wildcard [::] treated as CM_V6_DIR
- cm_add_v6_link: htons(port) was missing

Memory fixes:
- strdup→u_strdup in bridge (7 instances)
- u_realloc cap update before success check (3 instances)
- char sql[256]→[512] for truncated SELECT

Chat member hash now includes addresses for change detection

Linux chatgui:
- Link status dots in AccountList detail panel (1s poll)
- Self-node name in green in member list

tools/chatgui/src/memberlistmodel.cpp

@@ -34,6 +34,7 @@ QVariant MemberListModel::data(const QModelIndex& index, int role) const {
         if (role == Qt::ToolTipRole)
             return QString(it->online ? "online" : "offline") + " | 0x" +
                    QString("%1").arg(it->nodeId, 16, 16, QChar('0'));
+        if (role == Qt::UserRole + 2) return it->isSelf;
         return {};
     }
 
@@ -90,6 +91,7 @@ void MemberListModel::loadBatch(int from, int count) {
         int row = from + i;
         MemberListItem& item = m_cache[row];
         item.nodeId = members[i].nodeId;
+        item.isSelf = (item.nodeId == m_db->myNodeId());
         item.online = members[i].online;
         QString shortId = QString("%1").arg(members[i].nodeId, 8, 16, QChar('0')).right(4).toUpper();
         item.name = members[i].name.isEmpty() ? shortId : members[i].name;