Fix pagination alignment and refresh documentation

[arm092]

Summary

• fix overlapping desktop pagination controls and shifted hover backgrounds
• add stable sizing, focus states, and accessible pagination labels
• add a Chromium geometry regression and shared browser test server
• refresh the README layout, links, badges, compatibility section, and screenshot
• document the 3.2.3 patch release

Root cause

Desktop page buttons used negative horizontal margins inside nested divided containers. Their interactive boxes overlapped adjacent controls, so the hover background appeared offset from the visible page button.

Validation

• composer test -- --do-not-cache-result — 81 tests, 317 assertions
• npm run test:browser — 2 Chromium tests
• composer audit --locked — no advisories
• npm audit --audit-level=high — no vulnerabilities
• composer validate --strict
• git diff master...HEAD --check