Adapt page analytics layout and links

[thebuilder]

Summary

• reorder the Flags card after the other page analytics breakdowns
• center Flags at half width on wide desktops, pair it with Operating systems in the two-column layout, and restore full width on narrow screens
• link the page analytics site context directly to the resolved page URL while preserving the site-root link on global analytics
• add regression coverage for Flags ordering and document URL linking

Why

Removing the Pages card from document-scoped analytics changed CSS Grid auto-placement, leaving the remaining cards visually unbalanced. The Flags card also stretched too far on wide screens and wasted an available grid cell at the intermediate breakpoint. Separately, the header displayed the current hostname but always linked to the site root even though the resolved document route was already available.

Impact

Page analytics now uses the available space more intentionally across desktop, tablet, and mobile widths. Editors can also open the exact page they are reviewing directly from its analytics header.

Verification

• corepack pnpm build
• corepack pnpm test -- src/analytics/analytics-components.test.ts (105 tests passed)
• git diff --check