Improve iOS simulator destination reliability

[shai-almog]

Motivation

• Xcode 26 builds can fail intermittently when xcodebuild cannot see or match simulator destinations, so the script needs more robust destination selection and retry behaviour.

Description

• Added auto_select_destination_retry() to attempt auto_select_destination() up to 3 times with delays to reduce transient failure windows.
• Added destination_visible_to_xcodebuild() to verify the chosen destination is listed by xcodebuild and trigger re-selection if not.
• Prefer explicit platform=iOS Simulator,id=... destination strings (instead of id-only) for better stability with Xcode 26.
• Added build_with_destination() wrapper and added a retry path that re-selects a destination and retries xcodebuild when the build log contains "Unable to find a destination matching the provided destination specifier".
• All changes are in scripts/run-ios-ui-tests.sh and include additional informative logs when re-selection and retries occur.

Testing

• No automated tests were run on the modified script in this change.

---

Codex Task