Adopt 2027 Medicare-eligible Retiree Insured HMO and PPO Health Plan Rates; approve amendment 1 to Administrative Service Agreements with Humana Insurance Company, Kaiser Foundation Health Plan, Inc. and SCAN Health Plan for Medicare-eligible retiree health plans, 1/1/27 - 12/31/27; authorize County Procurement Officer or Deputized designee to execute amendments; and authorize Chief Human Resources Officer or designee to execute 2027 Group Service/Benefit Policies under certain conditions