docs(changelog): document @swc/jest migration and breaking changes

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

Author: samuelreichert

packages/pluggable-widgets-tools/CHANGELOG.md

@@ -19,6 +19,12 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 ### Changed
 
 -   We changed the order of imports in generated widget prop types to match that of the eslint sort-imports rule.
+-   We replaced `ts-jest` with `@swc/jest` as the Jest transform (3–5× faster for TSX-heavy test suites) and switched the test runner from `jest-jasmine2` to `jest-circus`. The default test timeout is now 10 000 ms (previously 5 000 ms).
+
+### Breaking Changes
+
+-   The `jest-jasmine2` runner has been removed. Tests using Jasmine-specific globals (`jasmine.createSpy()`, `jasmine.objectContaining()`, etc.) will throw `ReferenceError: jasmine is not defined`. Replace with Jest equivalents: `jest.fn()`, `expect.objectContaining()`.
+-   Consumers who extended the base config with `globals['ts-jest']` options must migrate those settings to the `@swc/jest` transform config.
 
 -   We silenced the Sass legacy JS API deprecation warning that appeared during widget bundling.