fix(gui-app): reduce retained tab-switch work

[tanveergill]

Summary

• avoid rerendering retained epic sidebars when only the parent activity surface changes
• preserve sidebar context and store-driven updates with focused regressions
• skip action-only worktree and slash-command queries for locked published-chat copies
• reduce the slow-direction observer-free second-rAF median from 122.5 ms to 100.9 ms while preserving live-chat and viewer behavior

The balanced pixel gate remained effectively unchanged, so this is intentionally scoped as a CPU and render-fan-out improvement rather than a complete fix for the observed pixel flash.

Related issue

No linked issue.

Checklist

• Pre-commit static checks pass
• Separate CI test checks pass
• Tests added/updated where it makes sense
• Commits are signed off per the DCO

[coderabbitai]

No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

⚙️ Run configuration

Configuration used: Repository UI (base), Organization UI (inherited)

Review profile: ASSERTIVE

Plan: Pro Plus

Run ID: d9c190ac-2b95-4ccf-b83d-117d3ad41526

📥 Commits

Reviewing files that changed from the base of the PR and between 22c33a3 and fe0fadb.

📒 Files selected for processing (8)

• clients/gui-app/src/components/epic-canvas/__tests__/epic-sidebar-column.test.tsx
• clients/gui-app/src/components/epic-canvas/renderers/__tests__/chat-tile-activation-query-policy.test.ts
• clients/gui-app/src/components/epic-canvas/renderers/__tests__/workspace-file-tile-read-validity.test.tsx
• clients/gui-app/src/components/epic-canvas/renderers/chat-tile-activation-query-policy.ts
• clients/gui-app/src/components/epic-canvas/renderers/chat-tile.tsx
• clients/gui-app/src/components/epic-canvas/sidebar/epic-sidebar-column.tsx
• clients/gui-app/src/components/epic-canvas/surface-host/__tests__/stable-tile-surface-host.test.tsx
• clients/gui-app/src/components/epic-canvas/surface-host/stable-tile-surface-host.tsx

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Summary by CodeRabbit

• Performance

  • Improved sidebar responsiveness by preventing unnecessary rerenders when surrounding content updates without changes.
  • Sidebar updates still respond immediately to width and session changes.

• Behavior Improvements

  • Chat data refreshes and command discovery now activate only when relevant, such as for visible, focused, or active chats.
  • Read-only published chat copies no longer trigger unnecessary background queries.
  • Hidden canvas tiles remain in place without being visually rendered, preserving layout geometry.

Walkthrough

The PR centralizes chat-tile query activation, memoizes EpicSidebarColumn, expands sidebar render tests, and applies opacity: 0 to hidden tile surface records.

Changes

Chat query activation

Layer / File(s)

Summary

Activation policy and chat-tile integration clients/gui-app/src/components/epic-canvas/renderers/chat-tile-activation-query-policy.ts, clients/gui-app/src/components/epic-canvas/renderers/chat-tile.tsx, clients/gui-app/src/components/epic-canvas/renderers/__tests__/chat-tile-activation-query-policy.test.ts, clients/gui-app/src/components/epic-canvas/renderers/__tests__/workspace-file-tile-read-validity.test.tsx

Chat-tile queries now use shared gates for live state, visibility, focus, activity, read-only state, and worktree binding. Tests cover the policy and editor readiness.

Sidebar rendering

Layer / File(s)	Summary
Memoized sidebar rendering and session switching clients/gui-app/src/components/epic-canvas/sidebar/epic-sidebar-column.tsx, clients/gui-app/src/components/epic-canvas/__tests__/epic-sidebar-column.test.tsx	EpicSidebarColumn is memoized. Tests cover stable parent props, width updates, and switching from loading to live hosts.

Surface presentation

Layer / File(s)	Summary
Hidden tile opacity clients/gui-app/src/components/epic-canvas/surface-host/stable-tile-surface-host.tsx, clients/gui-app/src/components/epic-canvas/surface-host/__tests__/stable-tile-surface-host.test.tsx	Hidden records receive invisible and opacity-0. Visible records remain without opacity-0.

Estimated code review effort: 3 (Moderate) | ~20 minutes

Merge Risk: ⚪ Minimal · up to fe0fa

This localized performance change is merge-ready after normal checks and review; no actionable merge-blocking risk remains.

Possibly related PRs

• traycerai/traycer#1009: Related chat-tile query activation changes.
• traycerai/traycer#1186: Related EpicSidebarColumn rendering and test changes.
• traycerai/traycer#903: Related StableTileSurfaceHost visibility behavior.

Suggested reviewers: anur4ag

Poem

A rabbit checks each query gate,
And keeps the sidebar light in state.
Hidden tiles fade from view,
Live chats wake when they should do.
Memoized hops make renders spry. 🐇

🚥 Pre-merge checks | ✅ 4 | ❌ 1

❌ Failed checks (1 warning)

Check name	Status	Explanation	Resolution
Docstring Coverage	⚠️ Warning	Docstring coverage is 0.00% which is insufficient. The required threshold is 80.00%.	Write docstrings for the functions missing them to satisfy the coverage threshold.

✅ Passed checks (4 passed)

Check name	Status	Explanation
Description check	✅ Passed	The description directly explains the rerender, query, surface-hiding, performance, and test changes in the pull request.
Title check	✅ Passed	The title clearly summarizes the primary change: reducing retained tab-switch work in the GUI app.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.

✨ Finishing Touches 💡 1

📝 Generate docstrings 💡

• Create stacked PR
• Commit on current branch

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Commit unit tests in branch traycer/mighty-bear-aa495f0eb818

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[tanveergill]

@codex review

[chatgpt-codex-connector]

Codex Review: Didn't find any major issues. 👍

Reviewed commit: ed96af6154

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[tanveergill]

@coderabbitai review

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[tanveergill]

@coderabbitai approve

[coderabbitai]

✅ Action performed

Comments resolved and changes approved.