feat(inbounds): add multi-select and bulk delete

Mirror the clients page: checkbox selection on the desktop table and on
mobile cards, with a danger Delete button in the toolbar that removes all
selected inbounds in one call.

Backend adds POST /panel/api/inbounds/bulkDel, which loops the existing
DelInbound per id (xray restarts at most once) and returns {deleted,
skipped}. Frontend shows a confirm modal plus a result toast, clears the
selection on success, adds bulk-delete i18n keys across all 13 languages,
and documents the endpoint in the in-panel API docs.

web/translation/es-ES.json

@@ -296,6 +296,10 @@
       "deleteConfirmContent": "Esto elimina el inbound y todos sus clientes. No se puede deshacer.",
       "resetConfirmTitle": "¿Restablecer el tráfico de \"{remark}\"?",
       "resetConfirmContent": "Restablece los contadores de subida/bajada a 0 para este inbound.",
+      "selectedCount": "{count} seleccionado(s)",
+      "selectAll": "Seleccionar todo",
+      "bulkDeleteConfirmTitle": "¿Eliminar {count} inbounds?",
+      "bulkDeleteConfirmContent": "Esto elimina los inbounds seleccionados y todos sus clientes. No se puede deshacer.",
       "cloneConfirmTitle": "¿Clonar el inbound \"{remark}\"?",
       "cloneConfirmContent": "Crea una copia con un puerto nuevo y una lista de clientes vacía.",
       "delAllClients": "Eliminar todos los clientes",
@@ -421,6 +425,8 @@
         "inboundsUpdateSuccess": "Entradas actualizadas correctamente",
         "inboundUpdateSuccess": "Entrada actualizada correctamente",
         "inboundCreateSuccess": "Entrada creada correctamente",
+        "bulkDeleted": "{count} inbounds eliminados",
+        "bulkDeletedMixed": "{ok} eliminados, {failed} fallidos",
         "inboundDeleteSuccess": "Entrada eliminada correctamente",
         "inboundClientAddSuccess": "Cliente(s) de entrada añadido(s)",
         "inboundClientDeleteSuccess": "Cliente de entrada eliminado",