feat(native-alarms): optional MesReportable column in the native-source override CSV import (ScadaBridge#102 item 4)

CLI import no longer has to reset MES overrides to inherit; a legacy 4-column file
still parses and the Central UI import keeps the stored flag for it.

Claude-Session: https://claude.ai/code/session_01GT67AEHd2Acv1YPwGfXEoV

src/ZB.MOM.WW.ScadaBridge.CentralUI/Components/Pages/Deployment/InstanceConfigure.razor

@@ -595,7 +595,7 @@
                     </small>
                 </div>
                 @* Bulk import of native alarm source retargets from a CSV
-                   (SourceName,Connection,SourceReference,Filter) — the SAME file
+                   (SourceName,Connection,SourceReference,Filter[,MesReportable]) — the SAME file
                    format and batch rules as the CLI
                    `instance native-alarm-source import --file`. Selecting a file
                    parses it with the shared NativeAlarmSourceOverrideCsvParser and
@@ -1886,7 +1886,10 @@
 
             await MutationServices.ExecuteConfigurationAsync(new SetInstanceNativeAlarmSourceOverridesCommand(Id,
                 outcome.Rows.Select(row => new NativeAlarmSourceOverrideEntry(row.SourceName, row.Connection, row.SourceReference, row.Filter,
-                    _existingNativeOverrides.GetValueOrDefault(row.SourceName)?.IsMesReportableOverride)).ToList()));
+                    // A file with the MesReportable column is authoritative; a legacy 4-column file keeps the stored flag.
+                    row.HasMesColumn
+                        ? row.MesReportable
+                        : _existingNativeOverrides.GetValueOrDefault(row.SourceName)?.IsMesReportableOverride)).ToList()));
             await OnInitializedAsync();
 
             _nasCsvImportSucceeded = true;