⚡ Bolt: Consolidate category and profile extraction for efficiency

[alazndy]

🎯 What:
Replaced chained declarative array operations (.map, .flatMap) inside multiple useMemo hooks with a single consolidated useMemo and an imperative O(N) for loop in CategoryFilterWidget.tsx.

💡 Why:
For large arrays of shortcuts, creating intermediate arrays via map and flatMap, and iterating the same list multiple times introduces unnecessary memory allocation (garbage collection overhead) and CPU cycles.

📊 Impact:

• Reduces execution time by ~54% (measured ~1.56ms -> ~0.71ms for 5000 items in standalone benchmark).
• Lowers memory footprint by eliminating intermediate throwaway arrays.
• Eliminates potential for processing empty s.category values.

🔬 Measurement:
Verified correctness via manual benchmark and TypeScript/Vite compilation build checks.

Benchmark Results (5000 items, 1000 iterations)

``` Old way: 1562.72 ms New way: 718.40 ms Improvement: 54.03% ```

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PR created automatically by Jules for task 15624599615633604726 started by @alazndy

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