Replaces the _quota_error/.response hack in workspaces.py with two
throwable OpenApiError subclasses (MemberLimitExceeded,
MemberLicenseExceeded) so all 403 quota responses flow through
OpenApiErrorFormatter rather than bypassing it via the early-return
in external_api.py. Wire codes rename to member_limit_exceeded and
member_license_exceeded.
Co-authored-by: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Co-authored-by: autofix-ci[bot] <114827586+autofix-ci[bot]@users.noreply.github.com>