GHSA-99pw-2v29-v4wc: Part-DB: Hardcoded APP_SECRET enables forged remember-me cookie

Part-DB is an open source inventory management system for electronic components. Prior to version 2.12.1, the file .env committed in the Part-DB repository contains a fixed value for APPSECRET (a03498528f5a5fc089273ec9ae5b2849). The official Docker image jbtronics/part-db1 does not override or randomize this value at container start-up. Because Symfony uses APPSECRET (via kernel.secret) as the HMAC key for signing remember-me cookies, any attacker who knows the secret -- or fetches it from the public repository -- can forge an arbitrary-user remember-me cookie and gain a fully authenticated session with no credentials required. This issue has been patched in version 2.12.1.