add server/client (S/C) indicator based on ETCP_LINK.is_server in connection monitor, member detail, and Android JSON

tools/chatgui-android/jni_bridge/android_jni_bridge.c

@@ -812,6 +812,14 @@ char* utun_bridge_get_member_detail_json(const char* channel_id, uint64_t node_i
     }
 
     char peers_tbl[80]; peers_table_name(channel_id, peers_tbl, sizeof(peers_tbl));
+
+    {   /* server/client role */
+        struct ETCP_CONN* detail_conn = NULL;
+        if (g_cc.inst) detail_conn = instance_find_conn(g_cc.inst, node_id);
+        const char* sc = (detail_conn && detail_conn->links)
+            ? (detail_conn->links->is_server ? "S" : "C") : "";
+        pos += (size_t)snprintf(buf + pos, sizeof(buf) - pos, ",\"sc\":\"%s\"", sc);
+    }
     snprintf(buf + pos, sizeof(buf) - pos, ",\"adr\":["); pos += strlen(buf + pos);
 
     if (sqlite3_prepare_v2(db,