refactor: localize footer copyright bar and about section labels/values
Add i18n keys for all footer text:
- Copyright bar: "Made with X lack of Y lots of Z by"
- Screen-reader text: love, sleep, coffee
- About section labels: role, cert, os, focus
- About section values: Cybersecurity Specialist, Slackware, OS year range, open-source ยท privacy
English and Italian translations provided.
All footer text now responds to language selection with no hardcoded strings.
