feat: add missing screenshots for labs 04, 05, and 07

- Lab 04: jscpd HTML duplication report (Playwright capture)
- Lab 05: coverlet output, JaCoCo output, coverage comparison
- Lab 07: complexity refactor, added tests, dedup utility

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Author: emmanuelknafo