Feat/agent task navigation

[ninime09]

feat: Agent Multi-Task Navigation System & Complete Status Architecture

Background

Cherry Studio V2's Agent workspace needs to support users managing multiple AI task threads simultaneously. The existing design relied on a sidebar session list for task switching, lacking a top-level quick-navigation entry point. The task status system was also incomplete (only active / completed / paused), unable to represent two critical real-world agent states: "waiting for user approval" and "execution error."

This PR delivers two core objectives:

1. Introduce a TaskBar (second toolbar row) enabling fast cross-task switching
2. Expand the task status system to a complete 5-state model, with consistent rendering across all display layers (TaskBar, main content header, history page)

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Motivation

Problem	Root Cause
Inefficient multi-task switching	Only the sidebar session list was available; no way to quickly scan global task status
Incomplete status model	waiting (pending approval) and error (execution failure) were missing, making it impossible to represent real agent execution states
Inconsistent status display	TaskBar, header text, and history page each resolved status independently, falling out of sync
Status data decoupled from content	AgentSession.status and WorkflowStep.status were two independent data sources, causing contradictions like "all steps done" in the content area while the header showed "Awaiting Approval"

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Before / After

Status System

Dimension	Before	After
AgentSession status values	active | completed | paused	active | waiting | error | paused | completed
WorkflowStep status values	done | running | pending	done | running | pending | error
TaskBar status dot	Green pulse for active only	5 states with distinct colors and animations
Header run-status label	Binary: active ? '运行中' : '已完成'	5-state label map
History page filter	All / Running (active only) / Completed	All / In Progress (aggregates all non-completed) / Completed
History page row indicator	Green dot for active only	5-state colored dots + tooltip

TaskBar (new)

Feature	Description
Task capsules	Show title, status dot, and pin indicator; hover reveals "title · status" tooltip
Filter views	Toggle between Recent Tasks and Pinned Tasks
Context menu	Inline rename, pin/unpin, branch from current task, close task (with adjacent-task navigation)
Drag to reorder	HTML5 native DnD with before/after insertion lines and clean state reset
Task branching	Auto-derives {base} - Branch / {base} - Branch 2 naming from existing branch count

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Changed Files:

File	Change Type	Description
src/app/types/agent.ts	Modified	AgentSession.status expanded to 5 states
src/app/types/chat.ts	Modified	WorkflowStep.status adds 'error'
src/styles/tailwind.css	Modified	Adds pulse-slow keyframe and animate-pulse-slow utility
src/app/context/AgentSessionContext.tsx	New	Shared agent session state; includes positional insert logic in reorderSessions
src/app/components/layout/TaskBar.tsx	New	Task navigation bar: status dots, context menu, inline rename, drag-to-reorder, branch creation
src/app/components/CherryStudio.tsx	Modified	Mounts AgentSessionProvider; conditionally renders TaskBar when Agent tab is active
src/features/agent/run/AgentRunPage.tsx	Modified	Migrates session state to Context; expands header status label to 5-state map; fixes CompactSessionSelector status dots
src/features/agent/run/SessionSidebar.tsx	Modified	Expands inline session status indicator to 5 states
src/features/agent/run/SessionHistoryPage.tsx	Modified	Refactors status filter to aggregate in-progress; expands row status dots to 5 states with tooltip
src/app/mock/agentData.ts	Modified	Aligns first 10 sessions' status with step data; adds complete error-state data for session-7

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Impact Assessment

Positive Impact:

• Users in multi-task scenarios can scan all task statuses directly from the TaskBar, reducing navigation depth
• waiting and error states are now clearly visible — users won't miss tasks that require confirmation or intervention
• All status display is driven by a single source of truth (AgentSession.status), eliminating cross-layer inconsistencies
• AgentSessionContext promotes session state from AgentRunPage-local to globally shared, establishing the foundation for future cross-component access

Potential Risks:

• AgentSession.status type expansion (waiting and error added): any existing exhaustive switch statements consuming this type elsewhere may need the two new cases added. All reference sites have been audited in this PR — no unhandled switches were found
• WorkflowStep.status adds error: WorkflowPanel.tsx's StatusDot already had a pre-existing error branch (red X icon) before this change; the type update activates it with no rendering logic changes required
• TaskBar drag-and-drop uses the HTML5 native DnD API — no new third-party dependencies, no bundle size impact

Feasibility Assessment

Dimension	Assessment
Technical implementation	Entirely within the existing stack (React + TailwindCSS v4 + Radix UI); no new dependencies introduced
Change scope	Well-contained: TaskBar and Context are new files; all modifications to existing components are minimal and targeted, with no unrelated refactoring
Backward compatibility	Status type changes are additive union extensions; existing consumers of active / completed / paused are unaffected
Mock data	Used for UI prototype only; does not affect real API integration; session status has been verified to match step/message content throughout
Status consistency	Verified across: session-1 (active), session-2 (completed), session-3 (completed), session-4 (waiting — last message unresolved), session-7 (error — final step is error)

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Known Gaps (follow-up)

• waiting / error / paused states currently require manual assignment in mock data; runtime auto-derivation from steps/messages back to AgentSession.status is not yet implemented
• completed status tasks have no confirmation dialog before closing (intentional design decision: closing a completed task is low-risk)
• queued state has been discussed but is not included in this PR; will be revisited once real concurrent execution requirements are confirmed