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/mainwindow.cpp

@@ -133,8 +133,9 @@ void MainWindow::setupNode() {
     connect(m_node, &UtunNode::error, this, [](const QString& msg) {
         qWarning("UtunNode error: %s", qPrintable(msg));
     });
-    connect(m_node, &UtunNode::started, this, []() {
+    connect(m_node, &UtunNode::started, this, [this]() {
         qDebug("UtunNode started");
+        if (m_accountList && m_node) m_accountList->setUtunInstance(m_node->instance());
     });
     connect(m_node, &UtunNode::stopped, this, [this]() {
         qDebug("UtunNode stopped");