fix: add Jest docblock pragma for ts-node compatibility

Add @jest-config-loader-options docblock pragma to Jest config files
that import other .ts files. This ensures ts-node compiles these files
with allowImportingTsExtensions enabled, which is required for .ts
extension imports to work.

The issue occurs because Jest v30 uses ts-node to compile TypeScript
config files, and ts-node registers with module: 'CommonJS' by default,
which doesn't allow .ts extensions in imports. The docblock pragma
passes compiler options to ts-node, enabling the required setting.

This fix ensures compatibility across all Node 22.x versions, including
versions prior to 22.18.0 which don't have native TypeScript support.

Tested with Node 22.17.1 and 22.20.0.

Author: kapral18

jest.config.all.ts

@@ -1,3 +1,6 @@
+/**
+ * @jest-config-loader-options {"compilerOptions":{"allowImportingTsExtensions":true}}
+ */
 import type { Config } from 'jest';
 import baseConfig from './jest.config.ts';
 

jest.config.mutation.ts

@@ -1,3 +1,6 @@
+/**
+ * @jest-config-loader-options {"compilerOptions":{"allowImportingTsExtensions":true}}
+ */
 import type { Config } from 'jest';
 import baseConfig from './jest.config.ts';
 

jest.config.private.ts

@@ -1,3 +1,6 @@
+/**
+ * @jest-config-loader-options {"compilerOptions":{"allowImportingTsExtensions":true}}
+ */
 import type { Config } from 'jest';
 import baseConfig from './jest.config.ts';