Empty ActiveSession launch controls now use both loaded chat messages and persisted session messageCount, so historical sessions do not briefly fall back into new-session launch mode while message history is still loading. Regression coverage also locks the first-message branch launch flows for direct checkout and isolated worktree sessions.
Constraint: Historical session lists already know messageCount before chat history finishes loading
Rejected: Wait for history fetch before rendering composer controls | it keeps the wrong new-session affordance visible during reopen
Confidence: high
Scope-risk: narrow
Directive: Branch/worktree launch controls are only for messageCount-zero sessions; reopened history must render repository context chips
Tested: bun run test -- --run src/components/chat/ChatInput.test.tsx src/pages/ActiveSession.test.tsx src/__tests__/pages.test.tsx
Tested: bun run check:desktop
Tested: agent-browser /tmp repo direct branch launch on /private/tmp/cc-haha-repo-e2e-IP9mkb produced session 9089ae96-5dd6-4ea6-b88e-376ab081ca24 on workDir /private/tmp/cc-haha-repo-e2e-IP9mkb
Tested: agent-browser /tmp repo isolated worktree launch produced session 9ec657bd-e503-48b3-b52f-36e210fc5d64 on workDir /private/tmp/cc-haha-repo-e2e-IP9mkb/.claude/worktrees/desktop-main-9ec657bd
Not-tested: root bun run verify; desktop surface was covered with check:desktop and live browser smoke
Empty active session tabs were still using the old directory-only picker, so sessions created from the sidebar lost the branch and worktree controls even when their workDir was a Git repository. Reuse the launch controls below the existing composer and replace only the empty session when the user changes repository launch options.
Constraint: Sidebar-created sessions land in ActiveSession, not the EmptySession landing view
Rejected: Reshape the whole session layout | the intended surface is only the controls below the composer
Confidence: high
Scope-risk: narrow
Directive: Keep repository launch controls shared between EmptySession and empty ActiveSession composer flows
Tested: bun run test -- --run src/__tests__/pages.test.tsx src/components/chat/ChatInput.test.tsx
Tested: bun run check:desktop
Tested: agent-browser sidebar new-session smoke at http://127.0.0.1:4790/ with screenshot /tmp/cc-haha-after-sidebar-new-session-controls.png
Not-tested: root bun run verify remains blocked by pre-existing root coverage gate outside desktop
The desktop workspace panel and chat transcript were mixing project-level file state with per-turn session history, which made rewind, file attachment, and changed-file previews brittle across multi-turn and historical sessions. This keeps turn checkpoints durable in the transcript, makes workspace refreshes happen at the right lifecycle points, and hardens long file previews without blocking the UI.
Constraint: Right-side workspace changes are project working-tree state, while chat turn cards are session checkpoint state.
Rejected: Treat every changed-file panel entry as session-local | new sessions must still reveal existing dirty project files.
Confidence: high
Scope-risk: moderate
Directive: Do not couple global workspace status to session checkpoint cards without preserving both product meanings.
Tested: cd desktop && bun run test src/components/workspace/WorkspacePanel.test.tsx
Tested: cd desktop && bun run lint
Tested: git diff --check
Tested: cd desktop && bun run test
Not-tested: Packaged Tauri runtime smoke test
