SIENTIAPDE-1430: Introduce static_threshold parameter for static window removal.

This parameter allows customizing the threshold (1-1000) used when rem_static_win is enabled, defaulting to 1 if null.
Updates include parameter definition, business rule validation, repository logic for passing the threshold, documentation in README.md and PIPELINE_PARAMS_CHANGELOG.md, and new unit and integration tests.

tests/utils/models/test_train_model_params.py

@@ -34,6 +34,7 @@ def valid_train_params_dict():
         'end_date': None,
         'scaler_name': 'Standard Scaler',
         'support_filters': {},
+        'static_threshold': None,
     }
 
 
@@ -564,3 +565,96 @@ def test_validate_business_rules_polynomial_regression_valid(valid_train_params_
     params = TrainModelParams.from_dict(valid_train_params_dict)
 
     params.validate_business_rules()  # Should not raise
+
+
+def test_validate_business_rules_static_threshold_valid(valid_train_params_dict):
+    """Test validate_business_rules accepts valid static_threshold when rem_static_win is True."""
+    from model_manager.utils.models.train_model_params import TrainModelParams
+
+    valid_train_params_dict['rem_static_win'] = True
+    valid_train_params_dict['static_threshold'] = 500
+    params = TrainModelParams.from_dict(valid_train_params_dict)
+
+    params.validate_business_rules()  # Should not raise
+
+
+def test_validate_business_rules_static_threshold_min_valid(valid_train_params_dict):
+    """Test validate_business_rules accepts static_threshold = 1."""
+    from model_manager.utils.models.train_model_params import TrainModelParams
+
+    valid_train_params_dict['rem_static_win'] = True
+    valid_train_params_dict['static_threshold'] = 1
+    params = TrainModelParams.from_dict(valid_train_params_dict)
+
+    params.validate_business_rules()  # Should not raise
+
+
+def test_validate_business_rules_static_threshold_max_valid(valid_train_params_dict):
+    """Test validate_business_rules accepts static_threshold = 1000."""
+    from model_manager.utils.models.train_model_params import TrainModelParams
+
+    valid_train_params_dict['rem_static_win'] = True
+    valid_train_params_dict['static_threshold'] = 1000
+    params = TrainModelParams.from_dict(valid_train_params_dict)
+
+    params.validate_business_rules()  # Should not raise
+
+
+def test_validate_business_rules_static_threshold_below_min(valid_train_params_dict):
+    """Test validate_business_rules raises error when static_threshold < 1."""
+    from model_manager.utils.models.train_model_params import TrainModelParams
+
+    valid_train_params_dict['rem_static_win'] = True
+    valid_train_params_dict['static_threshold'] = 0
+    params = TrainModelParams.from_dict(valid_train_params_dict)
+
+    with pytest.raises(ValueError, match='static_threshold must be between 1 and 1000, got 0'):
+        params.validate_business_rules()
+
+
+def test_validate_business_rules_static_threshold_above_max(valid_train_params_dict):
+    """Test validate_business_rules raises error when static_threshold > 1000."""
+    from model_manager.utils.models.train_model_params import TrainModelParams
+
+    valid_train_params_dict['rem_static_win'] = True
+    valid_train_params_dict['static_threshold'] = 1001
+    params = TrainModelParams.from_dict(valid_train_params_dict)
+
+    with pytest.raises(ValueError, match='static_threshold must be between 1 and 1000, got 1001'):
+        params.validate_business_rules()
+
+
+def test_validate_business_rules_static_threshold_none_when_rem_static_win_true(
+    valid_train_params_dict,
+):
+    """Test validate_business_rules accepts None static_threshold when rem_static_win is True."""
+    from model_manager.utils.models.train_model_params import TrainModelParams
+
+    valid_train_params_dict['rem_static_win'] = True
+    valid_train_params_dict['static_threshold'] = None
+    params = TrainModelParams.from_dict(valid_train_params_dict)
+
+    params.validate_business_rules()  # Should not raise - None is allowed
+
+
+def test_validate_business_rules_static_threshold_ignored_when_rem_static_win_false(
+    valid_train_params_dict,
+):
+    """Test validate_business_rules ignores static_threshold when rem_static_win is False."""
+    from model_manager.utils.models.train_model_params import TrainModelParams
+
+    valid_train_params_dict['rem_static_win'] = False
+    valid_train_params_dict['static_threshold'] = 5000  # Invalid value, but should be ignored
+    params = TrainModelParams.from_dict(valid_train_params_dict)
+
+    params.validate_business_rules()  # Should not raise - validation skipped
+
+
+def test_from_dict_static_threshold_type_error(valid_train_params_dict):
+    """Test from_dict raises TypeError when static_threshold has wrong type."""
+    from model_manager.utils.models.train_model_params import TrainModelParams
+
+    valid_train_params_dict['static_threshold'] = 'not_an_int'
+
+    with pytest.raises(TypeError, match='static_threshold must be of type int, but got str'):
+        TrainModelParams.from_dict(valid_train_params_dict)