auto-connect + GUI per-channel indicators

- chat_core_connect_auto: direct ETCP connect from SQLite (no BGP)
- auto_connect: parallel connect to peers with 3s timeout, retry 10s
- RTT saved to node_addresses on disconnect
- vertical status bar + circle badge with online count per channel
- ChannelListView prevents deselection

src/ntp_node_time.h

@@ -0,0 +1,35 @@
+#ifndef NTP_NODE_TIME_H
+#define NTP_NODE_TIME_H
+
+#include <stdint.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+struct UTUN_INSTANCE;
+
+#define NTP_NODE_MAX_PEERS 32
+
+#define NTP_NODE_DRIFT_WARN_US  2000000LL   // 2 seconds
+#define NTP_NODE_DRIFT_ERROR_US 10000000LL  // 10 seconds
+
+struct NTP_NODE_PEER {
+    uint64_t node_id;
+    int64_t  offset_us;   // my_time_recv - peer_time (positive = my clock ahead)
+};
+
+struct NTP_NODE_TIME {
+    struct NTP_NODE_PEER peers[NTP_NODE_MAX_PEERS];
+    int peer_count;
+};
+
+int  ntp_node_time_init(struct UTUN_INSTANCE* inst);
+void ntp_node_time_destroy(struct UTUN_INSTANCE* inst);
+void ntp_node_sync_peers(struct UTUN_INSTANCE* inst);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif // NTP_NODE_TIME_H