deps: add testing dependencies and update configuration

- Add Babel core, presets for env and TypeScript support
- Add babel-jest for JavaScript transformation in Jest
- Add node-fetch and @types/node-fetch for HTTP testing
- Update TypeScript config for better Jest compatibility
- Update bun.lock with new dependency resolutions

tsconfig.json

@@ -6,6 +6,8 @@
     "module": "ESNext",
     "lib": ["ES2022", "DOM", "DOM.Iterable"],
     "skipLibCheck": true,
+    "esModuleInterop": true,
+    "allowSyntheticDefaultImports": true,
     "types": ["node", "jest", "@playwright/test"],
     "moduleResolution": "bundler",
     "isolatedModules": true,