fix(chat_sync): peer online status not updated in invite flow

- cs_on_conn_up: call cs_on_peer_status_changed(peer,1) before return
  in invite path (was skipped, leaving inviter at online=0 in DB)
- cs_handle_welcome: remove unconditional set_online(0) — online
  status is managed by conn_up/conn_down, not by WELCOME
- cs_handle_welcome: add cs_post_channel_online() after WELCOME
  to send PEERS_ONLINE to GUI when channel is fully loaded
- cs_post_channel_online: add DEBUG log for PEERS_ONLINE event
- db_sync peer_check: suppress spam log when no peers connected

src/db_sync.c

@@ -1267,7 +1267,7 @@ static void db_sync_peer_check_cb(void* arg)
         return;
     }
 
-    int total_synced = 0, total_skipped = 0;
+    int total_synced = 0, total_skipped = 0, any_peers = 0;
     for (int i = 0; i < db->instance_count; i++) {
         struct DB_SYNC_INSTANCE* si = &db->instances[i];
         if (!si->enabled) continue;
@@ -1278,7 +1278,7 @@ static void db_sync_peer_check_cb(void* arg)
             struct TOPO_GROUP_CONN_ITEM* item = (struct TOPO_GROUP_CONN_ITEM*)e->data;
             if (item->conn && item->conn->peer_node_id != 0 && item->conn->links_up && item->conn->initialized) {
                 uint64_t pid = item->conn->peer_node_id;
-                if (pid != db->inst->node_id) { si_peer_add(si, pid); peers_found++; }
+                if (pid != db->inst->node_id) { si_peer_add(si, pid); peers_found++; any_peers = 1; }
             }
             e = e->next;
         }
@@ -1314,8 +1314,10 @@ static void db_sync_peer_check_cb(void* arg)
         }
     }
 
-    DEBUG_INFO(DEBUG_CATEGORY_DB_SYNC, "peer_check: instances=%d synced=%d skipped=%d",
-               db->instance_count, total_synced, total_skipped);
+    if (any_peers) {
+        DEBUG_INFO(DEBUG_CATEGORY_DB_SYNC, "peer_check: instances=%d synced=%d skipped=%d",
+                   db->instance_count, total_synced, total_skipped);
+    }
 
     db->peer_check_timer = uasync_set_timeout(db->inst->ua, DB_SYNC_PEER_CHECK_INTERVAL * 10000u,
                                                db, db_sync_peer_check_cb, "db_sync_peer");

tools/chatgui/transport/chat_sync.c

@@ -486,6 +486,7 @@ static void cs_post_channel_online(struct chat_sync* cs, const char* ch_id) {
     memcpy(evt + 1, ch_id, cl);
     uint16_t oc = (uint16_t)online; memcpy(evt + 1 + cl, &oc, 2);
     gui_bridge_post(GUI_EVT_CHANNEL_PEERS_ONLINE, evt, 1 + (int)cl + 2);
+    DEBUG_DEBUG(DEBUG_CATEGORY_DB_SYNC, "%s: PEERS_ONLINE ch=%.*s online=%d", CS_ID, (int)cl, ch_id, online);
 }
 
 /* ── Throttled sync (не чаще CS_SYNC_INTERVAL_MS) ── */
@@ -600,6 +601,8 @@ static void cs_on_conn_up(struct ETCP_CONN* conn, void* arg) {
         cs_send(g_cs, ch_id_str, peer, req, 1);
         g_cs->info_req_timer = uasync_set_timeout(g_cs->inst->ua,
             CS_INFO_REQ_TIMEOUT_MS * 10, g_cs, cs_info_req_timeout_cb, "cs_info_req");
+        DEBUG_INFO(DEBUG_CATEGORY_DB_SYNC, "%s: conn_up invite path, marking peer=%016llx online", CS_ID, (unsigned long long)peer);
+        cs_on_peer_status_changed(peer, 1);
         return;
     }
 
@@ -1336,7 +1339,6 @@ static void cs_handle_welcome(struct chat_sync* cs, uint64_t peer,
                            CS_ID, (unsigned long long)node_id, sid, port);
         }
         member_sync_cancel(g_cs->inst, node_id, ch_id);
-        member_sync_set_online(g_cs->inst, node_id, 0);
     }
 
     cs_refresh_channels(cs);
@@ -1360,6 +1362,8 @@ static void cs_handle_welcome(struct chat_sync* cs, uint64_t peer,
 
     gui_bridge_post(GUI_EVT_MEMBERS_CHANGED, evt, 1 + ch_id_len);
 
+    cs_post_channel_online(cs, ch_id);
+
     DEBUG_INFO(DEBUG_CATEGORY_DB_SYNC, "%s: WELCOME processed ch=%s peers=%d — message sync triggered via db_sync (active conn or peer_check timer every 5s)",
                CS_ID, ch_id, pc);
 }