feat(users): wire pruneDeadTokens into onUserDelete

functions/src/users/onUserDelete.ts

@@ -1,5 +1,6 @@
 import * as functions from 'firebase-functions'
 import * as admin from 'firebase-admin'
+import { pruneDeadTokens } from '../notifications/pruneTokens'
 
 /**
  * Auth deletion trigger — cascades account deletion server-side.
@@ -129,4 +130,6 @@ async function notifyPartner(
       console.warn(`[onUserDelete] FCM send to token ${tokens[i]} failed:`, result.reason)
     }
   })
+
+  await pruneDeadTokens(db, partnerId, tokens, sendResults)
 }