feat(feedback): implement shake gesture detection

[github-actions]

Note

The pull request "feat(feedback): implement shake gesture detection" was created by @antonis but did not reference an issue. Therefore this issue was created for better visibility in external tools like Linear.

📜 Description

Implements shake gesture detection for the user feedback form. When useShakeGesture is enabled in SentryUserFeedbackConfiguration, shaking the device opens the feedback form.

The implementation swizzles UIWindow.motionEnded:withEvent: using class_addMethod + method_setImplementation to safely intercept shake events without modifying UIResponder's inherited implementation. A cooldown of 1 second prevents duplicate triggers.

Note: this is exposed to be used on React Native too getsentry/sentry-react-native#5754

💡 Motivation and Context

The useShakeGesture property already existed in SentryUserFeedbackConfiguration but was never wired up. This PR implements the feature. The implementation is placed here (sentry-cocoa) rather than in each SDK separately so it can be reused by all SDKs that embed the feedback UI (React Native, Flutter, .NET MAUI, Unity).

💚 How did you test it?

• Tested in a sample iOS app (release build) — shaking the device opens the feedback form
• Debug builds: shake triggers the React Native dev menu (expected; RCTDevMenu also swizzles the same method)
• Unit tests added for SentryShakeDetector

📝 Checklist

• I added tests to verify the changes.
• No new PII added or SDK only sends newly added PII if sendDefaultPII is enabled.
• I updated the docs if needed.
• I updated the wizard if needed.
• Review from the native team if needed.
• No breaking change or entry added to the changelog.
• No breaking change for hybrid SDKs or communicated to hybrid SDKs.

[linear]

COCOA-1335