We are upgrading to Xcode 26.0.1 (Build 17A400). While Xcode itself installs correctly, tests running on Mac_arm64 bots are failing because the iOS 26.0 simulator runtime is not available.

The create_simulator step (or flutter build) fails with:
Error (Xcode): iOS 26.0 Platform Not Installed

Xcode Version: 26.0.1 (17A400)
Target: iOS 26.0 Simulator

Unlike the Intel bots (where iOS 26 is unsupported - #170294), these ARM bots can run the simulator, but the runtime component appears to be missing from the environment.

proposed fixes:
Fallback: Update create_simulator.sh to handle the specific runtime identifier for Xcode 26 if it differs from the default expectation (e.g., ensuring it falls back to the bundled iOS 26.0 release).