fix: Crash navigating to notification options - WPB-11062

[samwyndham]

Issue

When building using iOS 18 SDK on iOS 18 devices there is a crash when navigating to the notifications options screen. This is because we are dequeuing the footer from inside ConversationNotificationOptionsViewController.collectionView(_:layout:referenceSizeForFooterInSection:) which we should not be doing.

The fix is to create a separate sizing footer view that we only use for generating the reference size.

Testing

This must be tested using an Xcode 16 (iOS 18SDK) build on a iOS 18 device.

1. Navigate to any group conversation
2. Go to the details (by clicking the title)
3. Tap Notifications
4. There should be no crash and the footer is displayed correctly

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Checklist

• Title contains a reference JIRA issue number like [WPB-XXX].
• Description is filled and free of optional paragraphs.
• Adds/updates automated tests.

[github-actions]

Test Results

    2 files    294 suites   3m 45s ⏱️
1 812 tests 1 812 ✅ 0 💤 0 ❌
1 820 runs  1 820 ✅ 0 💤 0 ❌

Results for commit 2afefbf.

♻️ This comment has been updated with latest results.

[caldrian]

nice work!