[board] Use Unicode chess characters to Display Pieces

board/src/piece.rs

@@ -158,7 +158,22 @@ impl Piece {
 
 impl fmt::Display for Piece {
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
-        write!(f, "{}", self.shape)
+        let char = match (self.color, self.shape) {
+            (Color::White, Shape::Pawn) => '♟',
+            (Color::White, Shape::Knight) => '♞',
+            (Color::White, Shape::Bishop) => '♝',
+            (Color::White, Shape::Rook) => '♜',
+            (Color::White, Shape::Queen) => '♛',
+            (Color::White, Shape::King) => '♚',
+            (Color::Black, Shape::Pawn) => '♙',
+            (Color::Black, Shape::Knight) => '♘',
+            (Color::Black, Shape::Bishop) => '♗',
+            (Color::Black, Shape::Rook) => '♖',
+            (Color::Black, Shape::Queen) => '♕',
+            (Color::Black, Shape::King) => '♔',
+        };
+
+        write!(f, "{}", char)
     }
 }