feat: add AlphaBetaSearch and bot implementation with difficulty levels

docs/idea.md

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+Build a Scala 3 chess engine with these files: CoreTypes.scala, BitboardUtils.scala, MagicBitboards.scala, AttackTables.scala, GameState.scala, MoveGenerator.scala, ZobristHash.scala, AlphaBetaSearch.scala, Evaluation.scala, UciEngine.scala.
+
+Requirements:
+
+Use bitboards and magic bitboards for sliding pieces.
+Implement negamax alpha-beta search with transposition table, quiescence search, and MVV-LVA move ordering.
+Maintain Zobrist hashing for positions.
+Separate concerns: move generation, evaluation, search, and UCI handling.
+Produce a functional, efficient UCI engine in idiomatic Scala 3.