feat(updates): browse the changelog anytime and mark new releases

[Go2Engle]

Summary

Keep the changelog available in Settings → Updates even when CriProx is up to date or offline. Previously, release notes appeared only when an update was available. Releases now appear newest first, with New on versions newer than the running app and Installed on its current version. Downloading an update keeps it marked New until the installed app changes.

The accompanying screenshot refresh is in #110 under the repository's website release policy.

Type of Change

Feature

Technical Details

• Bundle the existing changelog with the desktop app and embed formatted, sanitized notes in the renderer's initial state so notes are available before a network check.
• Refresh history from published stable GitHub releases, merge notes by version, and preserve available history after failed checks.
• Keep history separate from installer availability; history failures do not block update checks or verified downloads.
• Reuse the existing changelog presentation and trusted link handling, with version labels and errors beside the affected release.
• Extend the local update simulation and add coverage for sorting, duplicate notes, stable-release filtering, version labels, offline access, and download state.
• Update the feature guide, installation guide, and README overview.

Testing Performed

• Application suite: 210 tests passed; the affected renderer tests also passed after the final link-error placement change.
• Application production build passed.
• Website suite: 17 tests passed; offline website build verified 12 pages and 20 releases.
• Playwright visual checks confirmed the up-to-date history and simulated newer-release badge.
• git diff --check passed.

npm test
npm run build
npm test --prefix site
npm run build --prefix site -- --offline

Breaking Changes

None. Installer selection, verification, and handoff behavior remain compatible.