Function getSectionTierKey

src/browser/utils/ui/workspaceFiltering.ts:898–904

(
  projectPath: string,
  sectionId: string,
  tierIndex: number
)

 * This is separate from project-level tiers to allow per-section age collapse.
 */
export function getSectionTierKey(
  projectPath: string,
  sectionId: string,
  tierIndex: number
): string {
  return `section:${projectPath}:${sectionId}:tier:${tierIndex}`;
}