Returns the authenticated caller's public identity (see MeResponse).

The authenticated caller's identity, returned by GET /api/v1/me. The public API authenticates two kinds of principal, so this is a type-discriminated shape. A "user" caller (a session/JWT user or a personal access token, ffp_...) carries email + emailVerified. A "service_token" caller (ffs_...) has no backing user row, so it carries organizationId + role + projectScope (the token's org, its role in that org, and its project allowlist) instead. The type-inapplicable fields are omitted from the response body. projectScope is omitted for an unrestricted service token (access to every project), never an empty list.