Review Scalekit code

Review a Scalekit snippet. Then stop. Do not write a new login.

Guardrails

• MUST review only. MUST NOT write a new login, callback, session, or logout.
• MUST open references/REFERENCE.md and references/COMMON-MISTAKES.md. Do not paste them here.
• MUST say "This method could not be verified" when a call is not in the reference or a live source.
• MUST NOT treat SCALEKIT_ENV_URL as valid. The env name is SCALEKIT_ENVIRONMENT_URL. Do not prepend https://.

Gotchas