fix(mcp): add description and certification fields to default list tool columns (#39017)

(cherry picked from commit 7be2acb2f3)

tests/unit_tests/mcp_service/dashboard/tool/test_dashboard_generation.py

@@ -87,6 +87,8 @@ def _mock_chart(id: int = 1, slice_name: str = "Test Chart") -> Mock:
     chart.datasource_name = None
     chart.datasource_type = None
     chart.description = None
+    chart.certified_by = None
+    chart.certification_details = None
     chart.cache_timeout = None
     chart.changed_by = None
     chart.changed_by_name = None

tests/unit_tests/mcp_service/dashboard/tool/test_dashboard_tools.py

@@ -529,13 +529,15 @@ class TestDashboardDefaultColumnFiltering:
             DASHBOARD_DEFAULT_COLUMNS,
         )
 
-        # Should have exactly 5 minimal columns
-        assert len(DASHBOARD_DEFAULT_COLUMNS) == 5
         assert set(DASHBOARD_DEFAULT_COLUMNS) == {
             "id",
             "dashboard_title",
             "slug",
+            "description",
+            "certified_by",
+            "certification_details",
             "url",
+            "changed_on",
             "changed_on_humanized",
         }