fix: resolve CI test failures

jest.config.js

@@ -0,0 +1,13 @@
+module.exports = {
+  preset: 'ts-jest',
+  testEnvironment: 'node',
+  roots: ['<rootDir>/tests'],
+  testMatch: ['**/*.test.ts'],
+  moduleFileExtensions: ['ts', 'js', 'json'],
+  collectCoverageFrom: [
+    'src/**/*.ts',
+    '!src/**/*.d.ts',
+  ],
+  coverageDirectory: 'coverage',
+  verbose: true,
+};