⚡ [Performance] Eliminate .Intersect() allocation overhead in local supply allocations

[google-labs-jules]

💡 What: Replaced LINQ .Intersect().ToList() with a manual foreach loop that checks .ContainsKey() in ApplyLocalAllocations within NetworkSimulationEngine and TemporalNetworkSimulationEngine.
🎯 Why: To eliminate the internal HashSet allocation, delegate overhead, and enumerator allocations of Intersect in a method called heavily during network routing calculations.
📊 Measured Improvement: Reduces GC pressure and memory allocation spikes during the supply/demand reconciliation phase.
🔬 Verification: All tests in MedWNetworkSim.Tests pass successfully.

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PR created automatically by Jules for task 14840035699391803862 started by @wnj00524

[google-labs-jules]

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