Block unsetting schema name for consistency

Author: deanhuynh

internal/provider/profiles_warehouse_resource.go

@@ -239,6 +239,15 @@ func (r *profilesWarehouseResource) Update(ctx context.Context, req resource.Upd
 		return
 	}
 
+	if (plan.SchemaName.IsNull() || plan.SchemaName.IsUnknown()) && !state.SchemaName.IsNull() {
+		resp.Diagnostics.AddError(
+			fmt.Sprintf("Unable to update Profiles Warehouse (ID: %s)", plan.ID.ValueString()),
+			"Cannot unset schema name",
+		)
+
+		return
+	}
+
 	// Only send schemaName to API if it differs from the remote state.
 	// This prevents API failures when the schema name already exists in the warehouse.
 	// The Segment API fails if we send a schemaName that matches the current configuration.