Fix action history pagination to avoid loading all results (#5005)

Previously, getGameHistory loaded all action results with history.all
then paginated in-memory. For games with many actions, this caused
timeouts.

Now uses history.since(startIndex).take(limit) which efficiently loads
only the save files containing the requested range. The since() method
in PersistedHistory already calculates which partial game files to read.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

src/main/scala/net/eagle0/eagle/service/EagleServiceImpl.scala

@@ -657,10 +657,10 @@ class EagleServiceImpl(
     gamesManager.gameControllerInfos.get(request.gameId) match {
       case Some(controllerInfo) =>
         val history    = controllerInfo.controller.engine.history
-        val allResults = history.all
+        val totalCount = history.count
 
         val startIndex = if request.startIndex > 0 then request.startIndex else 0
-        val limit      = if request.limit > 0 then request.limit else allResults.length
+        val limit      = if request.limit > 0 then request.limit else totalCount
 
         implicit val formats: DefaultFormats.type = DefaultFormats
         val monthNames                            = Vector(
@@ -678,11 +678,14 @@ class EagleServiceImpl(
           "November",
           "December"
         )
-        val entries                               = allResults.zipWithIndex
-          .drop(startIndex)
+        // Use since(startIndex) for efficient partial loading instead of loading all results
+        val entries                               = history
+          .since(startIndex)
           .take(limit)
+          .zipWithIndex
           .map {
-            case (actionWithState, index) =>
+            case (actionWithState, localIndex) =>
+              val index       = startIndex + localIndex
               val ar          = actionWithState.actionResult
               val gs          = actionWithState.gameState
               val actionJson  = writePretty(JsonFormat.toJson(ar))
@@ -708,7 +711,7 @@ class EagleServiceImpl(
 
         GetGameHistoryResponse(
           gameId = request.gameId,
-          totalActionCount = allResults.length,
+          totalActionCount = totalCount,
           entries = entries
         )