fixed

src/core/game/Game.ts

@@ -302,7 +302,7 @@ export class PlayerInfo {
   public readonly clan: string | null;
 
   constructor(
-    public readonly pattern: string | undefined,
+    public readonly pattern: string | null | undefined,
     public readonly flag: string | undefined,
     public readonly name: string,
     public readonly playerType: PlayerType,

src/core/game/GameView.ts

@@ -174,7 +174,7 @@ export class PlayerView {
     return this.data.flag;
   }
 
-  pattern(): string {
+  pattern(): string | undefined | null {
     return this.data.pattern;
   }