⚡ Bolt: Optimize DOM manipulation using DocumentFragment

[kaitoartz]

💡 What: Replaced direct DOM append operations within the createWorld loops with a DocumentFragment.
🎯 Why: Appending elements to a live DOM node inside a loop triggers expensive layout reflows per element. Using a DocumentFragment batches all the insertions into memory and appends them to the DOM in a single operation.
📊 Impact: Reduces layout reflows from O(N) to O(1) during the intensive initialization of the HyperScrollIntro sequence, preventing layout thrashing, improving load time, and preventing stutter on lower-end devices.
🔬 Measurement: Can be verified by measuring initialization time and reflow count in the browser performance profiler during page load.

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PR created automatically by Jules for task 15419422439028560651 started by @kaitoartz

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