Streak und Siegbonus nur für PvP-Runden; PvE friert die Streak ein

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

backend/tests/test_game.py

@@ -184,3 +184,11 @@ def test_ghost_source_takes_no_damage(art, cfg):
     game.step()
     drops = sum(1 for p in game.players if p.hp < hp_before[p.name])
     assert drops <= 4  # max. 3 Paar-Verlierer + 1 Ghost-Verlierer
+
+
+def test_pve_freezes_streak_and_pays_no_win_bonus(art, cfg):
+    game = Game(art, cfg, seed=4)
+    # Stage 1: drei PvE-Runden -> Streak bleibt 0
+    while game.round["stage"] == 1 and not game.over:
+        game.step()
+    assert game.player.streak == 0