Show unread activity on collapsed sidebar sections

[AaronGoldsmith]

Summary

• show a primary-color unread dot on collapsed custom, Channels, Forums, and Direct messages section headers
• scope each section's unread state and “Mark all as read” action to the channels it actually renders
• add Direct messages mark-all parity intentionally, while preserving Shift+Esc as the global mark-all shortcut
• include screen-reader text and collapsed/expanded behavior coverage

Slack uses a similar collapsed-section signal, providing precedent for this lightweight treatment. The dot is informational and appears only while a section is collapsed so it does not duplicate channel-row unread styling.

Testing

• pnpm exec biome check src/app/AppShell.tsx src/features/sidebar/ui/AppSidebar.tsx src/features/sidebar/ui/CustomChannelSection.tsx src/features/sidebar/ui/SidebarSection.tsx tests/e2e/channels.spec.ts
• pnpm typecheck
• pnpm exec playwright test tests/e2e/channels.spec.ts --project=smoke --grep "collapsed (custom|built-in) section" — 2 passed
• pnpm exec playwright test tests/e2e/channels.spec.ts --project=smoke — 63 passed before the review follow-ups; focused tests rerun afterward
• local pre-push desktop, Rust, and desktop-Tauri checks passed
• explicit DCO author/signoff identity check passed for both commits

Review notes

An adversarial review specifically challenged section scoping, collapsed-only rendering, accessibility, mark-all semantics, and whether the tests could pass with broken behavior. Follow-up changes scoped Channels/Forums actions to their rendered arrays, added expanded-state coverage, and added a positive Direct messages scoping case. A delta review found no remaining blockers.

Screenshots

Cropped sidebar screenshots are attached in this PR comment.

[chatgpt-codex-connector]

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[AaronGoldsmith]

Screenshots

Collapsed custom section — the unread dot appears in the collapsed custom-section header while unread channel rows remain visible in other sections.

Collapsed built-in section — the Channels header shows its scoped unread dot; Forums and Direct messages remain clear.

[chatgpt-codex-connector]

💡 Codex Review

Here are some automated review suggestions for this pull request.

Reviewed commit: 898027de04

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Your team has set up Codex to review pull requests in this repo. Reviews are triggered when you

• Open a pull request for review
• Mark a draft as ready
• Comment "@codex review".

If Codex has suggestions, it will comment; otherwise it will react with 👍.

Codex can also answer questions or update the PR. Try commenting "@codex address that feedback".