Module not found with component testing

[olivier65]

I have this project structure:

project_root
  node_modules
  src
    layouts
      Header.tsx
  playwright-ct-test
    layouts
      Header.test.tsx

In playwright-ct.config.ts testDir is set to ./playwright-ct-test. When I run npx run test-ct I get

Error: Cannot find module 'geojson'
Require stack:
- <project_root>\src\measurement\types.ts
- <project_root>\src\user\types.ts
- <project_root>\src\user\userReducer.ts
- <project_root>\src\rootReducers.ts
- <project_root>\src\configureStore.ts
- <project_root>\playwright-ct-test\layouts\Header.spec.tsx
- <project_root>\node_modules\@playwright\test\lib\loader.js
- <project_root>\node_modules\@playwright\test\lib\runner.js
- <project_root>\node_modules\@playwright\test\lib\cli.js
- <project_root>\node_modules\playwright-core\lib\cli\cli.js
- <project_root>\node_modules\playwright-core\cli.js
- <project_root>\node_modules\@playwright\test\cli.js

   at ..\src\measurement\types.ts:1

> 1 | import { Feature, Point } from 'geojson'
    | ^

Now of course geojson and @types/geojson are installed (the application works fine). Why cannot Playwright or Vite resolve this module?