hub v0.55.0: accept offbox_enlarge_blocked event (Task 3a-fix delivery chain)

allowedEventTypes gains offbox_enlarge_blocked (was 400 at ingestion, dropping the customer email).
Deliberate NON-change: no customerMessages entry — the static map would discard the controller's
dynamic two-number Hungarian message (templates.go:129 fallback is correct). event_test acceptance +
400 red-proof; templates_offbox_test locks the raw-message fallback. manifest bumped to :0.55.0.

manifests/hub.yaml

@@ -125,7 +125,7 @@ spec:
     spec:
       containers:
         - name: hub
-          image: gitea.dooplex.hu/admin/felhom-hub:0.54.0
+          image: gitea.dooplex.hu/admin/felhom-hub:0.55.0
           ports:
             - containerPort: 8080
               name: http