feat: game session, turn system, lobby, and room events

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

game/lobby_test.go

@@ -0,0 +1,40 @@
+package game
+
+import "testing"
+
+func TestCreateRoom(t *testing.T) {
+	lobby := NewLobby()
+	code := lobby.CreateRoom("Test Room")
+	if len(code) != 4 {
+		t.Errorf("Room code length: got %d, want 4", len(code))
+	}
+	rooms := lobby.ListRooms()
+	if len(rooms) != 1 {
+		t.Errorf("Room count: got %d, want 1", len(rooms))
+	}
+}
+
+func TestJoinRoom(t *testing.T) {
+	lobby := NewLobby()
+	code := lobby.CreateRoom("Test Room")
+	err := lobby.JoinRoom(code, "player1")
+	if err != nil {
+		t.Errorf("Join failed: %v", err)
+	}
+	room := lobby.GetRoom(code)
+	if len(room.Players) != 1 {
+		t.Errorf("Player count: got %d, want 1", len(room.Players))
+	}
+}
+
+func TestJoinRoomFull(t *testing.T) {
+	lobby := NewLobby()
+	code := lobby.CreateRoom("Test Room")
+	for i := 0; i < 4; i++ {
+		lobby.JoinRoom(code, "player")
+	}
+	err := lobby.JoinRoom(code, "player5")
+	if err == nil {
+		t.Error("Should reject 5th player")
+	}
+}