some fixes

data_acq_and_processing/processing/locator/src/payload_builder.cpp

@@ -192,18 +192,22 @@ auto build_payload_json(
         });
     }
 
-    // Fix #48: stamp every packet with a numeric build-time generation
-    // (`gen`, epoch ms). A cached snapshot re-sent verbatim to a new client
-    // keeps its original `gen`, so a consumer can compute the snapshot's true
-    // age and flag a stalled pipeline (which `tim` alone cannot express, having
-    // no date and rolling over at midnight).
-    const Json root{
+    Json root{
         {"ver", protocol_version},
         {"tim", format_timestamp_now()},
-        {"gen", epoch_millis_now()},
         {"sts", status},
         {"obs", std::move(obs_array)},
     };
+
+    // `gen` is a build-time generation stamp (epoch ms) that lets a consumer compute
+    // a packet's true age and flag a cached/stalled snapshot — something `tim` cannot
+    // express, having no date and rolling over at midnight. It is currently NOT sent;
+    // set this flag to true to re-enable it (epoch_millis_now() is kept ready for that).
+    constexpr bool kEmitGenerationStamp = false;
+    if (kEmitGenerationStamp) {
+        root["gen"] = epoch_millis_now();
+    }
+
     return root.dump();
 }