List all API keys for the account. Key values are never returned after initial creation.
If the account is on a plan that does not include API access,
returns { keys: [], planRequired: "team" } with HTTP 200
(not an error).
Permission: account:manage_integrations (admin+ role, Team plan+)
Clerk session cookie. Authentication is handled by Clerk. Sign in at https://app.dacard.ai/sign-in to obtain a session.