Add Chat and Agent mode switch

[marksftw]

Summary

• add an accessible Chat/Agent mode switch below the Maple logo, replacing the standalone Agent Mode action
• animate the selected surface while keeping hover, focus, light/dark, and reduced-motion behavior consistent
• preserve the exact Chat location and sidebar state, and restore the last Agent session when switching modes
• keep feature availability stable and guard Agent async state across route remounts

mode-switch.mov

Testing

• bun test — 131 passing
• bun run typecheck
• bun run lint — 0 errors (12 existing warnings)
• bun run build
• git diff --check

Closes #638

Summary by CodeRabbit

• New Features

  • Added a streamlined switch between Chat and Agent modes.
  • Agent sessions now remember and restore the most recently selected session when available.
  • Sidebar open/closed state persists across navigation and mode changes.
  • Added smoother workspace transitions, including reduced-motion support.
  • Improved mobile and landscape layouts by automatically closing the sidebar when appropriate.

• Bug Fixes

  • Prevented deleted sessions from being restored.
  • Reduced duplicate navigation and stale state during workspace transitions.

[coderabbitai]

No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

⚙️ Run configuration

Configuration used: Organization UI

Review profile: CHILL

Plan: Pro

Run ID: 569562d5-e81e-41d3-8562-08fc3af20dad

📥 Commits

Reviewing files that changed from the base of the PR and between 9d90eaf and 6d69b51.

📒 Files selected for processing (12)

• frontend/src/components/AgentMode.tsx
• frontend/src/components/AuthenticatedHomeContent.tsx
• frontend/src/components/ProjectDetailView.tsx
• frontend/src/components/Sidebar.tsx
• frontend/src/components/UnifiedChat.tsx
• frontend/src/components/WorkspaceModeSwitch.test.tsx
• frontend/src/components/WorkspaceModeSwitch.tsx
• frontend/src/contexts/PersistentHomeNavigationContext.ts
• frontend/src/services/agentSessionSelection.test.ts
• frontend/src/services/agentSessionSelection.ts
• frontend/src/services/flags.test.ts
• frontend/src/services/flags.ts

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📝 Walkthrough

Walkthrough

Changes

Workspace navigation and session persistence

Layer / File(s)	Summary
Persistence contracts and cache reads frontend/src/contexts/PersistentHomeNavigationContext.ts, frontend/src/services/agentSessionSelection.*, frontend/src/services/flags.*	Adds persistent sidebar context, per-user agent-session memory, and synchronous settled feature-flag reads with coverage.
Provider and persistent sidebar integration frontend/src/components/AuthenticatedHomeContent.tsx, frontend/src/components/AgentMode.tsx, frontend/src/components/UnifiedChat.tsx, frontend/src/components/ProjectDetailView.tsx	Stores user-scoped navigation state and reuses sidebar state across workspace remounts, including compact-layout transitions and serialized project-root persistence.
Workspace mode switch and navigation frontend/src/components/WorkspaceModeSwitch.*, frontend/src/components/Sidebar.tsx	Replaces the standalone Agent Mode action with an accessible Chat/Agent switch, guarded navigation, transition completion, reduced-motion handling, and cached flag gating.
Agent session restoration and deletion frontend/src/components/AgentMode.tsx	Remembers selected sessions, restores them after history readiness, guards asynchronous updates after unmount, and broadcasts session deletion events.

Estimated code review effort: 4 (Complex) | ~60 minutes

Sequence Diagram(s)

sequenceDiagram
  participant User
  participant WorkspaceModeSwitch
  participant Sidebar
  participant AgentMode
  participant AgentSessionSelectionMemory
  User->>WorkspaceModeSwitch: select workspace mode
  WorkspaceModeSwitch->>Sidebar: request mode change
  Sidebar->>AgentMode: navigate to agent workspace
  AgentMode->>AgentSessionSelectionMemory: resolve remembered session
  AgentSessionSelectionMemory-->>AgentMode: return available session
  AgentMode->>AgentMode: load and remember selected session

Loading

Possibly related PRs

• OpenSecretCloud/Maple#607: Introduced related desktop Agent Mode integration and feature-flag gating.
• OpenSecretCloud/Maple#611: Introduced the persistent home navigation provider extended by this change.

Suggested reviewers: anthonyronning

Poem

I’m a rabbit with a sidebar bright,
Chat and Agent hop into sight.
Sessions remember where they’ve been,
Flags peek softly, fresh and keen.
Deleted trails fade from view—
A tidy burrow, tried and true.

🚥 Pre-merge checks | ✅ 4

✅ Passed checks (4 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The title clearly describes the main change: adding a Chat/Agent mode switch.
Linked Issues check	✅ Passed	The changes implement the requested Chat/Agent sidebar switch, accessibility, history restoration, and removal of the old Agent Mode action.
Out of Scope Changes check	✅ Passed	The additional persistence, session-selection, and flag updates all support the mode-switch behavior and do not appear unrelated.

✨ Finishing Touches

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Commit unit tests in branch codex/chat-agent-mode-switch

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[cloudflare-workers-and-pages]

Deploying maple with    Cloudflare Pages

Latest commit:	6d69b51
Status:	✅  Deploy successful!
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Branch Preview URL:	https://codex-chat-agent-mode-switch.maple-ca8.pages.dev

View logs

[devin-ai-integration]

✅ Devin Review: No Issues Found

Devin Review analyzed this PR and found no bugs or issues to report.

[AnthonyRonning]

Looks much better!