🧪 Add test for analyzeImageAlts with no images

[saurabhsharma2u]

🎯 What: The testing gap addressed
This PR adds a unit test for analyzeImageAlts to cover the scenario where the input HTML contains no img tags.

📊 Coverage: What scenarios are now tested

• Ensures analyzeImageAlts correctly returns counts of 0 for totalImages, missingAlt, and emptyAlt when no images are present in the HTML.

✨ Result: The improvement in test coverage

• Confirms the robustness of the image analysis function for pages without images.

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PR created automatically by Jules for task 4783777708590763546 started by @saurabhsharma2u

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