Prerequisites

• Upgrade 50% of iOS devices to iOS 18 #148971
• CP ci.yaml and configs to use Xcode 16, iOS 18 Simulator, and macOS 14 for beta and stable #148960
• CP iOS 18 fixes for beta and stable #148972 - may want to wait for one release to be successful with those changes before doing this

Instructions

CP the following:

• Update .ci.yaml in flutter/flutter to use iOS 17 or 18 #148968