chatgui: fix ERROR→WARN/DEBUG for normal situations

- member_sync apply_items: empty payload is normal sync completion, not error
- topo_node_sqlite node_load: no addresses is normal for stub/seed nodes
- conn_mgr_core: node skipped when not in routing (normal for nodes w/o addrs)
- topo_group send_nodeinfo: downgrade ERROR→WARN in DEBUG category
- db_sync INIT_RESP: protocol details belong in DEBUG, not INFO

src/routing_layer/topo_node_sqlite.c

@@ -674,7 +674,7 @@ struct TOPO_NODE* topo_node_sqlite_node_load(sqlite3* db, struct TOPO_GROUPS* gr
             sqlite3_finalize(s);
         }
     }
-    if (!v4_head && !v6_head) { u_free(name); DEBUG_ERROR(DEBUG_CATEGORY_BGP, "node_load: node 0x%016llx has no addresses", (unsigned long long)node_id); return NULL; }
+    if (!v4_head && !v6_head) { u_free(name); DEBUG_WARN(DEBUG_CATEGORY_BGP, "node_load: node 0x%016llx has no addresses (may be stub/seed — will retry when addresses arrive)", (unsigned long long)node_id); return NULL; }
 
     struct TOPO_NODE* ni = u_calloc(1, sizeof(struct TOPO_NODE));
     if (!ni) { u_free(name); return NULL; }