Docs: refresh widget previews and pages for 1.17.0

[SandObserver]

Summary

• Refresh public/widgets/ and public/js/ from app v1.17.0 with npm run sync-widgets: redesigned System Summary, GitHub and digital clock, the city-light connections map, sideways wheel paging and the restore and import fixes.
• System Summary: the medium size adds charts and is the only size with the network row; add the Update Every setting; describe pointing at a chart or a disk.
• GitHub: describe the contribution day tooltip and the theme-following card.
• Add an invented CPU and RAM history to the w-stats stub so the medium preview draws full charts.

Releases with SandObserver/Stackyard v1.17.0. Merge after #95 and #96 or alongside them; they describe the same release.

Testing
npm run build and npm run check pass. Checked the GitHub, System Summary, Clock, Connections, Backup and Disk Health previews in Chromium in light and dark: every frame renders, no console errors.

Checklist

• npm run build and npm run check both pass.
• Product UI is shown by running or capturing it, never recreated in CSS.
• Any new preview or screenshot carries no private hostnames or real data.
• Visual changes verified in both colour schemes and both docs themes.
• Links to the app repo still resolve.

[cloudflare-workers-and-pages]

Deploying stackyard-docs with    Cloudflare Pages

Latest commit:	0d83f48
Status:	✅  Deploy successful!
Preview URL:	https://bcb819c3.stackyard-docs.pages.dev
Branch Preview URL:	https://docs-release-1-17-0-refresh.stackyard-docs.pages.dev

View logs