v5.4.0: scan history, scan reports and the dashboard

The last planned release of the toolkit.

• Every finished scan is saved, shown again on the Saved Scans page, compared port by port, and managed from the CLI (scan --history, --show, --compare, --delete).
• A saved scan's HTML report: the ports to look at first, each CVE with how it was found, printable to PDF from the browser (scan --report).
• The home page is a dashboard: the scans and their risks beside the saved runs and the session.

1,982 automated tests pass on Windows 10 with Python 3.14. Linux and macOS are not tested yet.

What changed: CHANGELOG · How it was checked: gate record