Fix import order in fallback tests per review feedback

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Co-authored-by: codewithdark-git <144595403+codewithdark-git@users.noreply.github.com>

Author: Copilot

tests/test_architecture_fallback.py

@@ -3,8 +3,8 @@
 
 import transformers
 
-import quantllm.core.turbo_model as turbo_model_module
 from quantllm.core.turbo_model import TurboModel
+import quantllm.core.turbo_model as turbo_model_module
 
 
 class _DummySmartConfig(SimpleNamespace):