Draft: [trigEGam] Integration beteween mongroups and TrigEgammaMonitoring

This MR is to include mongroups inside the TrigEgammaMonitoring framework.

• A method was implemented in the TrigEgammaMonitCategoryMT reading, for now, the mongoups from JSON local file produced by a ART test.
• At this moment, only the primary chains was configured, and then, called inside the TrigEgammaMonitorConfigMT.py file .
• In a next MR, we will include a logic to route chains to shifter and expert folders automatically, according to their respective mongroups.

JIRA Ticket: ATR-25841 .

ping: @safarzad , @cjmeyer , @fernando , @kyjones and @jlieberm

Generators/Pythia8_i/src/Pythia8_i.cxx

@@ -619,9 +619,16 @@ StatusCode Pythia8_i::fillWeights(HepMC::GenEvent *evt){
 
   // The following depends on the specific hepmc2/3 implementation
 #ifdef HEPMC3
-  if (!evt->run_info()) evt->set_run_info(m_runinfo);
+  if (!evt->run_info()) {
+     evt->set_run_info(m_runinfo);
+}
   evt->run_info()->set_weight_names(m_weightNames);
 
+// for the first event, weight AUX_bare_not_for_analyses is not present in evt->weights(), so we need to book a place for it by hand
+  if (m_internal_event_number == 1 && evt->run_info()->weight_names().size() == evt->weights().size()+1 ) {
+     evt->weights().push_back(1.0);
+}
+
   // added conversion GeV ->  MeV to ensure correct units
   evt->set_units(HepMC3::Units::MEV, HepMC3::Units::MM);