⚡ Bolt: [performance improvement] Optimize Temporal Context Copy Dictionary Allocations

.jules/bolt.md

@@ -88,3 +88,6 @@
 ## 2026-06-15 - Optimize Multiple ToDictionary Allocations inside Workspace UI
 **Learning:** In C#, executing multiple LINQ `.ToDictionary()` allocations on the same source collection (like building 9 different actor metrics dictionaries from `SimulationActors`) inside UI metric generation code allocates massive amounts of redundant enumerators, delegates, and intermediate dictionary structures on the UI thread, causing unnecessary memory allocation and garbage collection pauses.
 **Action:** Replace multiple `.ToDictionary()` allocations on identical source collections with a single manual `foreach` loop that populates pre-allocated dictionaries simultaneously. This transforms an O(K*N) allocation into a tight O(N) loop and completely avoids LINQ overhead.
+## 2024-05-31 - [Optimize ToDictionary with manual Dictionary copy constructor]
+**Learning:** In C#, replacing `context.Supply.ToDictionary(pair => pair.Key, pair => pair.Value, Comparer)` with the native dictionary copy constructor `new Dictionary<string, double>(context.Supply, Comparer)` avoids multiple LINQ enumerator allocations and delegate creations for the hot `ToRoutingContext` path inside `TemporalNetworkSimulationEngine`.
+**Action:** Replace direct `.ToDictionary` invocations with `new Dictionary(source, Comparer)` when copying dictionaries where the source implements `IDictionary<TKey, TValue>`.

src/MedWNetworkSim.App/Services/TemporalNetworkSimulationEngine.cs

@@ -1072,9 +1072,9 @@ private static RoutingTrafficContext ToRoutingContext(TemporalTrafficContext con
             Seed = context.Seed,
             NodesById = context.NodesById,
             ProfilesByNodeId = context.ProfilesByNodeId,
-            Supply = context.Supply.ToDictionary(pair => pair.Key, pair => pair.Value, Comparer),
-            SupplyUnitCosts = context.SupplyUnitCosts.ToDictionary(pair => pair.Key, pair => pair.Value, Comparer),
-            Demand = context.Demand.ToDictionary(pair => pair.Key, pair => pair.Value, Comparer),
+            Supply = new Dictionary<string, double>(context.Supply, Comparer),
+            SupplyUnitCosts = new Dictionary<string, double>(context.SupplyUnitCosts, Comparer),
+            Demand = new Dictionary<string, double>(context.Demand, Comparer),
             MeetingDemandEligibleNodeIds = context.MeetingDemandEligibleNodeIds
         };
     }