fix(go): collapse gb32960 auxiliary snapshot

go/vehicle-gateway/internal/realtime/repository.go

@@ -482,14 +482,19 @@ func normalizeGB32960RealtimeParsed(parsed map[string]any) {
 	}
 	for _, unit := range units {
 		unitMap, ok := unit.(map[string]any)
-		if !ok || strings.TrimSpace(strconvAny(unitMap["name"])) != "gd_fc_stack" {
+		if !ok {
 			continue
 		}
 		value, ok := unitMap["value"].(map[string]any)
 		if !ok {
 			continue
 		}
-		collapseGDFCStackValue(value)
+		switch strings.TrimSpace(strconvAny(unitMap["name"])) {
+		case "gd_fc_stack":
+			collapseGDFCStackValue(value)
+		case "gd_fc_auxiliary":
+			collapseGDFCAuxiliaryValue(value)
+		}
 	}
 }
 
@@ -528,6 +533,20 @@ func isGDFCStackFragmentField(key string) bool {
 	}
 }
 
+func collapseGDFCAuxiliaryValue(value map[string]any) {
+	subsystems, ok := asAnySlice(value["subsystems"])
+	if !ok || len(subsystems) == 0 {
+		return
+	}
+	latest := subsystems[len(subsystems)-1]
+	subsystem, ok := latest.(map[string]any)
+	if !ok {
+		return
+	}
+	value["subsystem_count"] = 1
+	value["subsystems"] = []any{cloneMap(subsystem)}
+}
+
 func fieldTimes(fields map[string]any, eventMS int64) map[string]int64 {
 	out := make(map[string]int64, len(fields))
 	for key := range fields {