feat: add result tracking to GameContext and update GameEngine for game outcomes

modules/core/src/main/scala/de/nowchess/chess/engine/GameEngine.scala

@@ -2,7 +2,7 @@ package de.nowchess.chess.engine
 
 import de.nowchess.api.board.{Board, Color, Piece, PieceType, Square}
 import de.nowchess.api.move.{Move, MoveType, PromotionPiece}
-import de.nowchess.api.game.{DrawReason, GameContext}
+import de.nowchess.api.game.{DrawReason, GameContext, GameResult}
 import de.nowchess.chess.controller.Parser
 import de.nowchess.chess.observer.*
 import de.nowchess.chess.command.{CommandInvoker, MoveCommand, MoveResult}
@@ -60,6 +60,7 @@ class GameEngine(
 
       case "draw" =>
         if currentContext.halfMoveClock >= 100 then
+          currentContext = currentContext.withResult(Some(GameResult.Draw(DrawReason.FiftyMoveRule)))
           invoker.clear()
           notifyObservers(DrawEvent(currentContext, DrawReason.FiftyMoveRule))
         else
@@ -222,12 +223,15 @@ class GameEngine(
 
     if ruleSet.isCheckmate(currentContext) then
       val winner = currentContext.turn.opposite
+      currentContext = currentContext.withResult(Some(GameResult.Win(winner)))
       notifyObservers(CheckmateEvent(currentContext, winner))
       invoker.clear()
     else if ruleSet.isStalemate(currentContext) then
+      currentContext = currentContext.withResult(Some(GameResult.Draw(DrawReason.Stalemate)))
       notifyObservers(DrawEvent(currentContext, DrawReason.Stalemate))
       invoker.clear()
     else if ruleSet.isInsufficientMaterial(currentContext) then
+      currentContext = currentContext.withResult(Some(GameResult.Draw(DrawReason.InsufficientMaterial)))
       notifyObservers(DrawEvent(currentContext, DrawReason.InsufficientMaterial))
       invoker.clear()
     else if ruleSet.isCheck(currentContext) then notifyObservers(CheckDetectedEvent(currentContext))

modules/core/src/test/scala/de/nowchess/chess/engine/GameEngineOutcomesTest.scala

@@ -1,7 +1,7 @@
 package de.nowchess.chess.engine
 
 import de.nowchess.api.board.Color
-import de.nowchess.api.game.DrawReason
+import de.nowchess.api.game.{DrawReason, GameResult}
 import de.nowchess.chess.observer.*
 import org.scalatest.funsuite.AnyFunSuite
 import org.scalatest.matchers.should.Matchers
@@ -23,6 +23,7 @@ class GameEngineOutcomesTest extends AnyFunSuite with Matchers:
     engine.processUserInput("d8h4")
 
     observer.hasEvent[CheckmateEvent] shouldBe true
+    engine.context.result shouldBe Some(GameResult.Win(Color.Black))
 
   test("checkmate with white winner"):
     val engine   = EngineTestHelpers.makeEngine()
@@ -42,6 +43,7 @@ class GameEngineOutcomesTest extends AnyFunSuite with Matchers:
     val evt = observer.getEvent[CheckmateEvent]
     evt.isDefined shouldBe true
     evt.get.winner shouldBe Color.White
+    engine.context.result shouldBe Some(GameResult.Win(Color.White))
 
   // ── Stalemate ───────────────────────────────────────────────────
 
@@ -78,6 +80,7 @@ class GameEngineOutcomesTest extends AnyFunSuite with Matchers:
     val evt = observer.getEvent[DrawEvent]
     evt.isDefined shouldBe true
     evt.get.reason shouldBe DrawReason.Stalemate
+    engine.context.result shouldBe Some(GameResult.Draw(DrawReason.Stalemate))
 
   test("stalemate board is not reset after draw"):
     val engine   = EngineTestHelpers.makeEngine()
@@ -189,6 +192,7 @@ class GameEngineOutcomesTest extends AnyFunSuite with Matchers:
     val evt = observer.getEvent[DrawEvent]
     evt.isDefined shouldBe true
     evt.get.reason shouldBe DrawReason.FiftyMoveRule
+    engine.context.result shouldBe Some(GameResult.Draw(DrawReason.FiftyMoveRule))
 
   test("draw cannot be claimed when not available"):
     val engine   = EngineTestHelpers.makeEngine()
@@ -216,3 +220,4 @@ class GameEngineOutcomesTest extends AnyFunSuite with Matchers:
     val evt = observer.getEvent[DrawEvent]
     evt.isDefined shouldBe true
     evt.get.reason shouldBe DrawReason.InsufficientMaterial
+    engine.context.result shouldBe Some(GameResult.Draw(DrawReason.InsufficientMaterial))