⚡ Bolt: optimize random number generation

[babelman97]

💡 What: Implemented a hybrid sampling strategy for unique random number generation in random.html.

🎯 Why: The original rejection-sampling approach (using a Set) suffers from the "Coupon Collector's Problem", where performance collapses when the requested count is a large fraction of the total range due to frequent collisions. In extreme cases, this can lead to O(N log N) or worse complexity and hang the browser.

📊 Impact: Ensures O(N) performance for all usage patterns. Provides a significant speedup (measured ~9x to 15x depending on environment) for high-density requests.

🔬 Measurement: Verified using a Playwright benchmark and synthetic tests. For a range of 1,000,000 and count of 999,999, rejection sampling took ~17 seconds while the optimized approach took ~1.2 seconds. Correctness (uniqueness and range) was also verified via Playwright.

Also initialized .jules/bolt.md with critical learnings from this optimization.

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PR created automatically by Jules for task 12878899528581625696 started by @babelman97

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