Improve the revert process for Firefox settings by extending
modifications to also include `prefs.js`.
- Validate profile directories similarly to execution script.
- Check and warn if Firefox is running during revert to prevent
`prefs.js` from being overriden.
- Clarify output messages for execution and revert scripts.
- Add flowchart diagram for visual documentation.
- Improve documentation for consistency and precision.
- Update `.gitignore` to account for temporary draw.io files.
