add Preview callout for JSONPath (#19600)

* add vector indexing and JSONPath to feature availability page

Author: taroface

src/current/v25.2/cockroachdb-feature-availability.md

@@ -47,6 +47,14 @@ Any feature made available in a phase prior to GA is provided without any warran
 **The following features are in preview** and are subject to change. To share feedback and/or issues, contact [Support](https://support.cockroachlabs.com/hc).
 {{site.data.alerts.end}}
 
+### Vector indexes
+
+A [vector index]({% link {{ page.version.version }}/vector-indexes.md %}) enables efficient approximate nearest neighbor (ANN) search on high-dimensional [`VECTOR`]({% link {{ page.version.version }}/vector.md %}) columns. Use vector indexes to improve the performance of similarity searches over large datasets, such as embeddings generated by machine learning models.
+
+### JSONPath queries
+
+[JSONPath]({% link {{ page.version.version }}/jsonpath.md %}) expressions and functions can be used to query and filter [`JSONB`]({% link {{ page.version.version }}/jsonb.md %}) data, using [JSONPath expressions]({% link {{ page.version.version }}/jsonpath.md %}#jsonpath-expression) as arguments in [JSONPath functions]({% link {{ page.version.version }}/jsonpath.md %}#jsonpath-functions).
+
 ### Triggers
 
 [Triggers]({% link {{ page.version.version }}/triggers.md %}) are in Preview. A trigger executes a function when one or more specified SQL operations is performed on a table. Triggers respond to data changes by adding logic within the database, rather than in an application. They can be used to modify data before it is inserted, maintain data consistency across rows or tables, or record an update to a row.

src/current/v25.2/jsonpath.md

@@ -5,6 +5,10 @@ toc: true
 docs_area: reference.sql
 ---
 
+{{site.data.alerts.callout_info}}
+{% include_cached feature-phases/preview.md %}
+{{site.data.alerts.end}}
+
 {% include_cached new-in.html version="v25.2" %} JSONPath expressions and functions are used to query and filter [`JSONB`]({% link {{ page.version.version }}/jsonb.md %}) data. A [JSONPath expression](#jsonpath-expression) is a string that identifies one or more elements in a JSON document, and is used as a [JSONPath function](#jsonpath-functions) argument.
 
 ## JSONPath expression