fix: hide device topup button when no HWID packages or unlimited devices

backend/bot/app/web/webapp/serializers.py

@@ -193,6 +193,7 @@ def _serialize_subscription(
     can_topup_regular_traffic = False
     can_topup_premium_traffic = False
     can_topup_traffic = False
+    can_topup_devices = False
     if settings.tariffs_config and active.get("tariff_key"):
         try:
             tariff = settings.tariffs_config.require(str(active.get("tariff_key")))
@@ -204,10 +205,16 @@ def _serialize_subscription(
                 and tariff.premium_topup_packages.has_any()
             )
             can_topup_traffic = bool(can_topup_regular_traffic or can_topup_premium_traffic)
+            # max_devices == 0 means unlimited — top-up is pointless in that case.
+            can_topup_devices = bool(
+                tariff.has_hwid_device_packages()
+                and _coerce_int_or_none(active.get("max_devices")) != 0
+            )
         except Exception:
             can_topup_regular_traffic = False
             can_topup_premium_traffic = False
             can_topup_traffic = False
+            can_topup_devices = False
 
     return {
         "active": seconds_left > 0,
@@ -249,6 +256,7 @@ def _serialize_subscription(
         "can_topup_traffic": can_topup_traffic,
         "can_topup_regular_traffic": can_topup_regular_traffic,
         "can_topup_premium_traffic": can_topup_premium_traffic,
+        "can_topup_devices": can_topup_devices,
         "period_start_at": active.get("period_start_at").isoformat()
         if active.get("period_start_at")
         else None,