Improve task UI responsiveness and optimistic task updates

[ssshanaka]

Motivation

• Reduce UI jank and unnecessary recomputation when switching views or updating tasks to make interactions feel instant.
• Make adding tasks and subtasks feel fast by avoiding full list reloads and replacing DOM query focus patterns with a stable input ref.
• Reduce rerenders caused by board/list derivations and item rendering during sync/status changes.

Description

• Memoized derived lists and trees in the list view by adding visibleTasks, completedTasks, listTaskCounts, and currentTaskList using useMemo in src/pages/AppPage.jsx to avoid rebuilding trees on unrelated renders.
• Reworked board rendering in src/components/TaskBoard.jsx to precompute boardData with useMemo and exported TaskBoard with React.memo to cut unnecessary recalculation and rerenders.
• Replaced DOM queries/timeouts for focusing the add-task input with a stable ref and a focusAddTaskInput callback (requestAnimationFrame) in src/pages/AppPage.jsx, and wired that into sidebar/board actions and keyboard shortcuts.
• Improved add-task and subtask UX by keeping optimistic local entries and then replacing them with the server response (instead of forcing a full getTasks reload), added saveTasksCache helper to persist optimistic state, and exported DesktopTaskItem with React.memo to further reduce rerenders (src/pages/AppPage.jsx, src/components/TaskBoard.jsx, src/components/DesktopTaskItem.jsx).

Testing

• npm run build — succeeded and produced a production build.
• npm test -- --watchAll=false — failed early due to the CRA/Jest environment not resolving react-router-dom in src/App.jsx (pre-existing resolver issue), so unit tests did not run to completion.

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Project	Deployment	Actions	Updated (UTC)
taskflow-nih3	Ready	Preview, Comment	Jun 26, 2026 6:15pm

[chatgpt-codex-connector]

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[chatgpt-codex-connector]

Avoid caching another list after async adds

When a user submits a task in list A and switches to another list before insertTask resolves, the prev passed to this updater can now be the new list's tasks while currentListId is still the old list captured by the submit handler. This saves the other list into list A's cache and leaves the temp task unreplaced until a later network refresh; only write the cache when the temp id is still present, or update a per-list snapshot instead of the shared tasks state.

Useful? React with 👍 / 👎.

[chatgpt-codex-connector]

Keep sidebar counts in sync with list edits

These badges now depend only on allTasksByList, but list-view add/complete/delete handlers update the separate tasks state and do not update allTasksByList. After a user edits tasks while viewing a list, the sidebar count for that list stays based on the last board fetch until returning to board or refreshing, so the displayed count is stale; include the active list state in this derivation or keep allTasksByList updated with the same optimistic changes.

Useful? React with 👍 / 👎.