fix: Chatterbox uses separate classes per variant, remove turbo

ChatterboxTTS and ChatterboxMultilingualTTS are separate classes.
Turbo variant doesn't exist in chatterbox-tts 0.1.7.
Multilingual generate() requires language_id parameter.

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

kischdle/llmux/tests/test_config.py

@@ -5,8 +5,8 @@ def test_load_models_config_returns_physical_and_virtual():
     physical, virtual = load_models_config()
     assert isinstance(physical, dict)
     assert isinstance(virtual, dict)
-    assert len(physical) == 9
-    assert len(virtual) == 16
+    assert len(physical) == 8
+    assert len(virtual) == 15
 
 
 def test_physical_model_has_required_fields():