⚡ Optimize redundant array allocation in Heatmap component

[artosien]

💡 What: Replaced the array map + spread operator usage with a single reduce() operation when calculating maxFreq in the Heatmap component.
🎯 Why: The previous approach (Math.max(...numbers.map(...))) creates an intermediate array containing only the frequencies, which wastes memory and adds garbage collection overhead. Further, using the spread operator on a large array can potentially cause a call stack size exceeded error. The reduce() implementation computes the maximum in a single pass without extra allocations.
📊 Measured Improvement:
Using a standalone benchmark node script doing 1,000,000 iterations over an array of 58 objects:

• Baseline (map + max): 882.84ms
• Optimized (reduce): 152.64ms
• Improvement: ~82.7% reduction in execution time (approx 5.8x speedup)

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PR created automatically by Jules for task 17136021111186621730 started by @artosien

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