Function tierFromLookupKey

server/src/db/organization-db.ts:214–220

(lookupKey: string | null | undefined)

 * Matches the tier portion of keys like "aao_membership_professional_250".
 */
export function tierFromLookupKey(lookupKey: string | null | undefined): MembershipTier | null {
  if (!lookupKey) return null;
  for (const [prefix, tier] of LOOKUP_KEY_TIERS) {
    if (lookupKey.startsWith(prefix)) return tier;
  }
  return null;
}

/**
 * Input shape for `resolveMembershipTier`. Kept as a named type so the