Updates a pool's name or openCaseRiskLevels; omit a field to leave it unchanged. The name must be non-empty and unique in your organization. openCaseRiskLevels replaces the whole set and must name levels bound in the pool's risk configs; an empty list clears it. The change applies to future risk changes only and never opens cases for members already at an in-set level. Config-to-level bindings are immutable.