feat(clients,routing): label inbounds by remark with tag fallback

Inbound pickers and chips across the Users area, the inbounds attach-clients modals, and the routing rule inbound-tags selector showed the auto-generated tag (in-443-tcp). Show the inbound remark when set, falling back to the tag.

Only display labels change; option values keep using the inbound id (or tag for routing rules, which match inbounds by tag), so filtering, attaching, and saved rules are unaffected. Routing reads remarks via a shared useInboundOptions hook that reuses the existing options query cache.

frontend/src/pages/clients/ClientFormModal.tsx

@@ -261,9 +261,9 @@ export default function ClientFormModal({
     () => (inbounds || [])
       .filter((ib) => MULTI_CLIENT_PROTOCOLS.has(ib.protocol || ''))
       .map((ib) => ({
-        label: ib.tag ?? '',
+        label: ib.remark?.trim() || ib.tag || '',
         value: ib.id,
-        title: ib.tag ?? '',
+        title: ib.remark?.trim() || ib.tag || '',
       })),
     [inbounds],
   );