fix: warn on contract.enforced=true for materialized_view (#1279)

Upstream dbt does not support contracts on materialized views
(https://docs.getdbt.com/docs/mesh/govern/model-contracts). dbt-databricks
was silently accepting the flag, hiding yml/SQL drift. Now emits a warning
pointing at the dbt docs. Strictly additive; existing build outcomes and
constraint behavior are unchanged.

Co-authored-by: Isaac

Author: sd-db

CHANGELOG.md

@@ -1,3 +1,9 @@
+## dbt-databricks 1.11.8 (TBD)
+
+### Fixes
+
+- Warn when `contract.enforced: true` is set on a `materialized_view` model ([#1279](https://github.com/databricks/dbt-databricks/issues/1279))
+
 ## dbt-databricks 1.11.7 (Apr 17, 2026)
 
 ### Features

dbt/include/databricks/macros/relations/materialized_view/create.sql

@@ -24,6 +24,9 @@
   {%- set model_columns = model.get('columns', {}) -%}
   {%- set contract_config = config.get('contract') -%}
   {%- if contract_config and contract_config.enforced -%}
+    {%- do exceptions.warn(
+         "model '" ~ model.name ~ "' sets contract.enforced=true, but contracts are not supported for materialized_view. See https://docs.getdbt.com/docs/mesh/govern/model-contracts"
+       ) -%}
     {%- set model_constraints = model.get('constraints', []) -%}
   {%- else -%}
     {%- set model_constraints = [] -%}