Simplify Jest setup

- Remove explicit dependency on jest-circus: this is now the default runner
- Remove test timeout setting
- Remove @types/jest from explicit dependencies

jest.config.js

@@ -3,10 +3,8 @@ module.exports = {
   moduleFileExtensions: ['js', 'ts', 'json'],
   testEnvironment: 'node',
   testMatch: ['**/*.test.ts'],
-  testRunner: 'jest-circus/runner',
   transform: {
     '^.+\\.ts$': 'ts-jest'
   },
-  verbose: true,
-  setupFilesAfterEnv: ['./jest.setup.js']
+  verbose: true
 }