test scrolling screenshots

[TheSecurityDev]

Attempt at scrolling screenshots (this PR is for testing the UI previews)

[github-actions]

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[Copilot]

Pull Request Overview

This PR implements scrolling screenshot functionality for UI testing by adding the ability to capture multiple screenshots while scrolling through content until no more changes are detected.

• Added capture_scrollable method that takes multiple screenshots while scrolling and compares them to detect when content stops changing
• Added helper method screenshot_with_suffix for saving screenshots with custom suffixes
• Integrated scrolling capture into the main test flow with fallback to single screenshots

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