Screenshots not rendering in README.md

## Description

Some screenshots in the README (`app-homepage.jpeg` and `timetable-view.jpeg`) are not rendering correctly.

## Steps to Reproduce

1. Open the repository on GitHub.
2. Navigate to `README.md`.
3. Notice that the screenshots are missing or not displayed.

## Expected Behavior

- All screenshots should be visible and correctly displayed in the README.
- Relative paths should point to the correct location, and the image files should be committed to the repository.

## Additional Notes

- The images are stored in the `assets/` folder at the root of the repository.
- File names and extensions are **case-sensitive** (`app-homepage.jpeg`, `timetable-view.jpeg`).

Verifique o arquivo README.md em busca de links de imagens que apontem para assets/app-homepage.jpeg e assets/timetable-view.jpeg. Confirme que os arquivos de imagem existem na pasta assets/ com a capitalização e a extensão corretas. Atualize os caminhos Markdown, se necessário, e depois visualize o README no GitHub para confirmar que as capturas de tela são renderizadas.

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