fix: decode native SQL view metadata (#4785)

View APIs now read the native `name`, `query`, and `schema` columns
returned by `CREATE VIEW` and `DESCRIBE VIEW`. The schema JSON carries
the defining database and namespace; the requested namespace identifies
where the view lives. The unreleased JSON-envelope response is removed
without a compatibility fallback.

```python
view = db.create_view("adults", "SELECT name FROM people WHERE age >= 18")
view = db.describe_view("adults")
```

```sql
CREATE VIEW "adults" AS SELECT name FROM people WHERE age >= 18;
DESCRIBE VIEW "adults";
```

Both Python calls execute SQL through the query-backed job adapter and
wait on the resulting query. A job handle uses that query's `id` and
type `query`; reading metadata consumes its completed result rather than
resubmitting the DDL. Creation returns the definition from the creating
execution, with no extra describe request.

docs/web/sql/ddl/view.mdx

@@ -30,10 +30,14 @@ FROM "documents" AS t1
 INNER JOIN "categories" AS t2 ON t1.ints = t2.ints
 ```
 
-The statement returns one UTF-8 `definition` column containing JSON with the
-view name, namespace, original query, default database and namespace, and its
-Arrow schema resolved at creation time. `DESCRIBE VIEW "recent_matches"`
-returns the same metadata shape. Anything the
+The statement returns one row with UTF-8 `name`, `query`, and `schema` columns.
+`query` contains the stored query, including any declared column aliases, and
+`schema` contains its Arrow schema as JSON. The schema metadata keys
+`lancedb::view::default_db` and `lancedb::view::default_namespace` identify the
+defining database and namespace. The root namespace is `public`; nested
+namespace components are separated by `$`.
+
+`DESCRIBE VIEW "recent_matches"` returns the same metadata shape. Anything the
 [dialect](/sql/functions) supports can define one: joins, predicates,
 aggregates, window functions.
 
@@ -65,9 +69,8 @@ SHOW VIEWS
 SHOW VIEWS IN "analytics" WHERE name > 'previous_view' LIMIT 100
 ```
 
-`SHOW VIEWS` returns ascending `name` values and a nullable `location` column.
-Locations are populated only when the deployment exposes catalog locations.
-The `name` cursor is scoped to the selected namespace.
+`SHOW VIEWS` returns ascending `name` values. The `name` cursor is scoped to
+the selected namespace.
 
 Object commands retain their small results in shared storage even when general
 query-result copying is disabled, so asynchronous polling can use any query node.