feat: Phase 6b/6c - Tab/Panel Switching & Real-time Progress Streaming for Background Tasks

[roomote-v0]

This PR attempts to address Issue #12330 (Phase 6b: Tab/Panel Switching). Feedback and guidance are welcome.

Summary

Implements Phase 6b of the parallel agent execution enhancement, building on top of Phase 6a (conversation replay). This adds a dedicated BackgroundTaskView as a full tab in the webview, with navigation between a task list and the replay view.

What's included

New components:

• BackgroundTaskView -- Full-tab container managing navigation between sub-views (list and replay)
• BackgroundTasksList -- Displays subtasks from task history with status badges (Running/Completed/Delegated), mode labels, timestamps, and cost info

Tab infrastructure:

• New bgTask tab type in App.tsx with routing
• backgroundTasksButtonClicked command registered in package.json (sidebar overflow menu + editor title menu)
• Command handler in registerCommands.ts that sends action to webview
• Type updates in @roo-code/types for the new action and tab values

Navigation flow:

1. User clicks "Background Tasks" in the sidebar/editor overflow menu
2. App switches to tab === "bgTask" showing BackgroundTaskView
3. BackgroundTaskView starts on BackgroundTasksList (task list with status indicators)
4. Clicking a task navigates to BackgroundTaskReplayView (from Phase 6a)
5. "Back" button returns to the task list; "Back to chat" returns to the foreground task

Key design decisions:

• Foreground task state is preserved (ChatView remains mounted with isHidden)
• Background tasks are filtered from taskHistory by parentTaskId presence
• Current foreground task is excluded from the background tasks list
• Ready for Phase 6c (BackgroundTaskLiveView) -- sub-view routing is extensible

Tests

30 tests across 5 test files (all passing):

• BackgroundTasksList.spec.tsx (8 tests) -- empty state, filtering, click handling, status badges, truncation
• BackgroundTaskView.spec.tsx (5 tests) -- list/replay navigation, header visibility, close behavior
• App.spec.tsx (2 new tests) -- bgTask tab switching and return to chat
• Existing Phase 6a tests remain green (7 replay + 3 backend = 10 tests)

What's deferred to Phase 6c+

• Real-time progress streaming (BackgroundTaskLiveView)
• Active task badge/count on the tab icon
• Write-capable background tasks + file locking (Phase 7)
• Persistent background task history (Phase 7)

Interactively review PR in Roo Code Cloud

[easonLiangWorldedtech]

@roomote-v0[bot]

Thanks for opening PR #12346 for Phase 6b.

From the description, it looks like it follows the confirmed design (full BackgroundTaskView tab, navigation via overflow menu, BackgroundTasksList filtered by parentTaskId, preserving foreground state, and reusing the replay view from 6a).

Next step proposal:

Please proceed with Phase 6c: Real-time Progress Streaming next, following the minimal viable scope we confirmed earlier (tool name + status only, last-N rolling window, 500ms throttle, only for the currently viewed background task).

You can open a new PR for 6c when ready. After 6c is done, we can mark 6a and 6b as ready for review together.

Let me know if you see any blockers or need to adjust the scope of 6c before starting.

[roomote-v0]

Fixaroo   See task

Implemented Phase 6c: Real-time Progress Streaming for background tasks. All local checks (lint, type-check, 43 tests) passed.

_{View commit | Revert commit}

[easonLiangWorldedtech]

@roomote please update the pr title, 6b and 6c is in same pr.

[roomote-v0]

Fixaroo   See task

Updated PR title to feat: Phase 6b/6c - Tab/Panel Switching & Real-time Progress Streaming for Background Tasks to reflect that both Phase 6b and 6c are included in this PR.

[roomote-v0]

Closing as part of PR restructuring per issue #12330. This work will be combined into the new Remaining Phases (4+5+6) PR with proper stacked branching.