Improve sidebar clarity and tag navigation

[adulau]

Motivation

• Make the right-hand sidebar widgets (search, categories, tags) clearer, less noisy, and more accessible while addressing layout and readability issues visible in the screenshot.
• Reduce visual clutter from a very long tag list by surfacing the most-used tags and providing a clear path to the full index.

Description

• Replace the right-column wrapper div with a semantic, labelled <aside> in layouts/_default/list.html and layouts/_default/single.html to improve structure and accessibility.
• Rework the tags widget in layouts/partials/widgets/tags.html to render a labelled <section>, show the top 24 tags sorted by usage using the taxonomy .ByCount, link via each tag's .Page.RelPermalink, display usage counts, and add a "Browse all tags" link to the full index.
• Add a comprehensive set of styles to static/css/custom.css to style sidebar panels, headings, search input groups, readable wrapping tag “chips”, hover/active/focus states, and responsive spacing for tablet/mobile.
• Improve ARIA/semantic affordances (IDs, aria-labelledby, decorative icon semantics) so the sidebar is keyboard- and screen-reader-friendly.

Testing

• Ran git diff --check and it reported no whitespace/patch errors (success).
• Executed a structural Python check that verified balanced CSS braces in static/css/custom.css and matching <aside>/</aside> pairs in the modified templates (success).
• Attempted to init/update the theme submodule with git submodule update --init --recursive but the repository fetch failed due to the environment network proxy returning HTTP 403 (unable to validate theme rendering).
• Attempted to install screenshot tooling with npx playwright but npm registry access returned HTTP 403, so visual screenshot testing could not be run in this environment.

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Codex Task

[chatgpt-codex-connector]

Codex Review Summary

This comment shows the latest Codex review activity on this pull request.

Review	Status	Commit	Review trigger
📝 Code Review	✅ Completed 2026-09-29T07:53:58.952366Z	7c27e93	PR opened
🔒 Security Review	✅ Completed 2026-09-29T07:55:04.282916Z	7c27e93	PR opened

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