fix(sql-lab): correct createCtasDatasource return type and fix latent bug

Address codeant/bito review on #40037. The /api/v1/dataset/get_or_create/
endpoint returns { result: { table_id: number } } per its OpenAPI schema,
but createCtasDatasource was annotated as Promise<{ id: number }> and
passed json.result straight into createDatasourceSuccess (which builds
`${data.id}__table`). The result.id read was always undefined, so the
CTAS Explore flow has been silently constructing "undefined__table" as
the datasource identifier at runtime. The previous as-unknown-as cast in
ExploreCtasResultsButton hid the contract drift from TypeScript.

- createCtasDatasource now returns Promise<{ table_id: number }>, matching
  the actual API payload.
- Normalize result.table_id -> { id } when dispatching
  createDatasourceSuccess, so the existing reducer/action contract is
  preserved (createDatasource still calls it with a real { id }).
- Drop the cast in ExploreCtasResultsButton; data.table_id is now properly
  type-checked.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

superset-frontend/src/SqlLab/actions/sqlLab.ts

@@ -1712,7 +1712,7 @@ export function createDatasource(
 
 export function createCtasDatasource(
   vizOptions: Record<string, unknown>,
-): SqlLabThunkAction<Promise<{ id: number }>> {
+): SqlLabThunkAction<Promise<{ table_id: number }>> {
   return (dispatch: AppDispatch) => {
     dispatch(createDatasourceStarted());
     return SupersetClient.post({
@@ -1720,9 +1720,14 @@ export function createCtasDatasource(
       jsonPayload: vizOptions,
     })
       .then(({ json }) => {
-        dispatch(createDatasourceSuccess(json.result));
+        const result = json.result as { table_id: number };
+        // The endpoint's `result.table_id` IS the dataset id; normalize so
+        // createDatasourceSuccess's `${data.id}__table` resolves correctly.
+        // Without this, the CTAS Explore button silently produced
+        // `"undefined__table"` because `result.id` doesn't exist.
+        dispatch(createDatasourceSuccess({ id: result.table_id }));
 
-        return json.result;
+        return result;
       })
       .catch(() => {
         const errorMsg = t('An error occurred while creating the data source');

superset-frontend/src/SqlLab/components/ExploreCtasResultsButton/index.tsx

@@ -56,11 +56,7 @@ const ExploreCtasResultsButton = ({
   };
 
   const visualize = () => {
-    (
-      dispatch(createCtasDatasource(buildVizOptions)) as unknown as Promise<{
-        table_id: number;
-      }>
-    )
+    dispatch(createCtasDatasource(buildVizOptions))
       .then(data => {
         const formData = {
           datasource: `${data.table_id}__table`,