⚡ Bolt: Optimize KnowledgeGraph search and focus lookups

[hadsern]

💡 What: Pre-indexed id and title fields inside useMemo of KnowledgeGraph using .toLowerCase() onto new fields, alongside adding a Map for precise object lookup by id. Then refactored the keydown handler and suggestion filtering logic to use these pre-processed properties instead of continuously executing .toLowerCase() calls during string matching.

🎯 Why: Repeated string allocations and array traversals triggered by high-frequency inputs like key strokes (onKeyDown) and suggestion box render updates were creating significant CPU load due to the execution loop redundantly running .toLowerCase() inside every iteraton for each user stroke against a large array of nodes.

📊 Impact: Reduces computational overhead significantly by removing $O(N)$ string operations from the main rendering and input loops, converting search loops to use existing lowercased variables and focus resolutions into an $O(1)$ exact Map lookup.

🔬 Measurement: Verifiable by executing the React Profiler in developer tools and observing the render-phase durations and reduced heap allocations when actively typing within the 'Find' inputs inside the Graph page.

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PR created automatically by Jules for task 7406408528643236081 started by @hadsern

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