docs: add release blog for v1.14.2 (#1137)

Author: tasshi-me

website/blog/2025-08-06-cli-kintone-v1-14-2.md

@@ -0,0 +1,28 @@
+---
+slug: cli-kintone-v1-14-2
+title: cli-kintone v1.14.2
+authors: [tasshi, extensions-platform-team]
+tags: [release]
+---
+
+We are happy to announce the release of **cli-kintone v1.14.2** 🎉
+
+👉 [Download this version here](https://github.com/kintone/cli-kintone/releases/tag/v1.14.2)
+
+## What's new?
+
+### Server-side UPSERT is now the default behavior
+
+In [v1.13.0](./2025-01-16-cli-kintone-v1-13-0.md), we introduced the `--experimental-use-server-side-upsert` option to enable the `upsert` mode of the [Update Records](https://kintone.dev/en/docs/kintone/rest-api/records/update-records/) API.
+
+Starting with this release, server-side UPSERT is now the default behavior.
+It includes minor improvements over the experimental implementation.
+
+Depending on the execution conditions, this change may improve import performance and reduce the number of API requests.
+
+The `--experimental-use-server-side-upsert` option is now deprecated.  
+Specifying this option in this version will show a warning (not an error), but the option will be removed entirely in a future release.
+
+## Miscellaneous
+
+See the [changelog](https://github.com/kintone/cli-kintone/blob/main/CHANGELOG.md#1142-2025-08-06) for an exhaustive list of changes.