fix(tests): capture real __import__ before patching builtins to avoid recursion

fake_import closures that called __import__ directly would resolve to
themselves after patch("builtins.__import__") was applied, causing
RecursionError instead of the expected ImportError path. Capture
builtins.__import__ into _real_import before the patch context so the
fallthrough call uses the original import machinery.

Fixes test_import_error_raises_embeddings_unavailable and the same
pattern in test_debug_log_fires_before_raise_on_import_error.

Author: Zelys-DFKH

tests/test_coverage_iter235.py

@@ -356,13 +356,15 @@ def test_is_exception_subclass(self):
         assert isinstance(exc, Exception)
 
     def test_import_error_raises_embeddings_unavailable(self):
-        # Clear model cache to force a fresh load attempt.
+        import builtins as _b
+
         emb_mod._MODEL_CACHE.clear()
+        _real_import = _b.__import__
 
         def fake_import(name, *args, **kwargs):
             if name == "fastembed":
                 raise ImportError("no fastembed")
-            return __import__(name, *args, **kwargs)
+            return _real_import(name, *args, **kwargs)
 
         with patch("builtins.__import__", side_effect=fake_import), pytest.raises(
             EmbeddingsUnavailable, match="fastembed not installed"
@@ -387,12 +389,15 @@ def fake_find_spec(name, *args, **kwargs):
         assert result is False
 
     def test_debug_log_fires_before_raise_on_import_error(self):
+        import builtins as _b
+
         emb_mod._MODEL_CACHE.clear()
+        _real_import = _b.__import__
 
         def fake_import(name, *args, **kwargs):
             if name == "fastembed":
                 raise ImportError("no fastembed")
-            return __import__(name, *args, **kwargs)
+            return _real_import(name, *args, **kwargs)
 
         # Confirm the exception is EmbeddingsUnavailable — the debug log
         # may or may not fire depending on cache state, but the raise must happen.