Optimize ActionResultFilter with Set and ListBuffer (#5672)

- Change UNIVERSALLY_VISIBLE_TYPES from Vector to Set for O(1) contains
- Replace O(n²) Vector concatenation with O(n) ListBuffer in filterForPlayer

Co-authored-by: Claude Opus 4.5 <noreply@anthropic.com>

src/main/scala/net/eagle0/eagle/library/ActionResultFilter.scala

@@ -1,5 +1,7 @@
 package net.eagle0.eagle.library
 
+import scala.collection.mutable.ListBuffer
+
 import net.eagle0.eagle.library.actions.applier.ActionResultWithResultingState
 import net.eagle0.eagle.library.util.faction_utils.FactionUtils
 import net.eagle0.eagle.library.util.view_filters.GameStateViewFilter
@@ -12,7 +14,7 @@ import net.eagle0.eagle.model.view.game_state.GameStateViewDiff
 import net.eagle0.eagle.FactionId
 
 object ActionResultFilter {
-  private val UNIVERSALLY_VISIBLE_TYPES: Vector[ActionResultType] = Vector(
+  private val UNIVERSALLY_VISIBLE_TYPES: Set[ActionResultType] = Set(
     ActionResultType.GameStart,
     ActionResultType.StartBattle,
     ActionResultType.BattleEnded,
@@ -162,19 +164,22 @@ object ActionResultFilter {
       startingState: GameState,
       results: Vector[ActionResultWithResultingState],
       factionId: FactionId
-  ): Vector[ActionResultView] =
-    results
-      .foldLeft((startingState, Vector.empty[ActionResultView])) {
-        case ((gs, acc), res) =>
-          val maybeNewRes = filterOne(
-            startingState = gs,
-            result = res,
-            factionId = factionId
-          )
+  ): Vector[ActionResultView] = {
+    val accumulator  = ListBuffer.empty[ActionResultView]
+    var currentState = startingState
 
-          (res.resultingState, acc ++ maybeNewRes)
-      }
-      ._2
+    results.foreach { res =>
+      filterOne(
+        startingState = currentState,
+        result = res,
+        factionId = factionId
+      ).foreach(accumulator += _)
+
+      currentState = res.resultingState
+    }
+
+    accumulator.toVector
+  }
 
   def filterForObserver(
       startingState: GameState,