[Bitrise] Failover gracefully when run drifts from main

[kieran-osgood-shopify]

What changes are you making?

We had an issue where a branch contained the browserstack run plan changes but was stale behind main which had just merged support for swift/kotlin samples / e2e tests
This meant that the pipeline DAG was built from main, whilst the run plan was executed from the pre-merge PR head

A possible solution was to use the runplan from the PR HEAD rather than the pre-merge head but that would result in passing PR status and then failing on main, its not feasible to try and override, we can't change the DAG to be generated from the pre-merge state

The solution here is mostly just to fail gracefully, detect this drift, print a clear error, and provide the solution.

How to test

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Before you merge

Important

• I've added tests to support my implementation
• I have read and agree with the Contribution Guidelines
• I have read and agree with the Code of Conduct
• I've updated the relevant platform README (platforms/swift/README.md and/or platforms/android/README.md)

---

Releasing a new Swift version?

• I have bumped the version in ShopifyCheckoutKit.podspec
• I have bumped the version in platforms/swift/Sources/ShopifyCheckoutKit/ShopifyCheckoutKit.swift
• I have updated the SwiftPM/CocoaPods version snippets in platforms/swift/README.md (major version only)

Releasing a new Embedded Checkout Protocol version?

• I have bumped embeddedCheckoutProtocolAndroid in platforms/android/gradle/libs.versions.toml
• I have updated protocol/languages/kotlin/embedded-checkout-protocol/api/embedded-checkout-protocol.api if the public API changed

Releasing a new Android version?

• I have bumped checkoutKitAndroid in platforms/android/gradle/libs.versions.toml
• I have updated the Gradle/Maven version snippets in platforms/android/README.md

Tip

See the Contributing documentation for the full release process per platform.

[kieran-osgood-shopify]

• DO NOT MERGE: add phantom E2E target to simulate config/matrix drift #491
• [Bitrise] Failover gracefully when run drifts from main #490 👈 (View in Graphite)
• [Tophat] Adds swift/kotlin to tophat install rows #473
• [Tophat] feat: add the ability to wait for a build to complete #434
• [Tophat] Refactor: extract shared browserstack client #433
• [Tophat] Add Bitrise client for Tophat artifact discovery #419
• [Tophat] Add Tophat integration for Checkout Kit React Native builds #401
• [Phase 7] Soft-launch E2E PR checks #364 : 1 other dependent PR (#417 )
• [Phase 6] Report E2E results to GitHub #363
• [Phase 5] Run BrowserStack Maestro from E2E matrix rows #362
• [Phase 4] Build React Native iOS E2E IPA artifact #361
• [Phase 3] Build React Native Android E2E APK artifact #360
• [Phase 2] Add Bitrise E2E pipeline skeleton #357
• [Phase1] Add E2E matrix launch smoke foundation #356
• main

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[bitrise]

Install this build

Open Tophat, select your target device, then click Install. Links open on the Mac running Tophat.

SDK	Install
React Native	Install with Tophat
Swift	Install with Tophat
Kotlin	Install with Tophat

Checkout Kit E2E results

Status	Suite	Target	Platform	OS version tag	Device
✅	tests/shared/launch-smoke.yaml	react-native	ios	latest	iPhone 15 iOS 27 Beta
✅	tests/shared/launch-smoke.yaml	react-native	android	latest	Google Pixel 9 Android 17.0
✅	tests/shared/launch-smoke.yaml	kotlin	android	latest	Google Pixel 9 Android 17.0
✅	tests/shared/launch-smoke.yaml	swift	ios	latest	iPhone 15 iOS 27 Beta