fix: hide internal worktree branch labels

Desktop worktree sessions should show the source project and worktree marker without surfacing implementation refs like worktree-desktop-* as user-facing branch state. The git-info response now keeps launch branch metadata separate from worktree identity, and the desktop chip hides branch and slug labels in isolated worktree mode.

Constraint: Git worktrees need an internal branch for isolated execution, but that ref is product plumbing rather than useful UI context
Rejected: Show both launch branch and worktree slug | duplicated noisy identifiers and confused the session location
Confidence: high
Scope-risk: narrow
Tested: bun test src/server/__tests__/sessions.test.ts -t "git-info"; cd desktop && bun run test src/components/shared/ProjectContextChip.test.tsx; bun run check:server; bun run check:desktop; git diff --check
Not-tested: Live desktop screenshot smoke

desktop/src/components/shared/ProjectContextChip.test.tsx

@@ -4,7 +4,7 @@ import '@testing-library/jest-dom'
 import { ProjectContextChip } from './ProjectContextChip'
 
 describe('ProjectContextChip', () => {
-  it('keeps the source project label and adds worktree identity', () => {
+  it('shows only the source project label and worktree marker for isolated worktrees', () => {
     render(
       <ProjectContextChip
         workDir="/workspace/OpenCutSkill/.claude/worktrees/desktop-main-54a09f85"
@@ -17,9 +17,9 @@ describe('ProjectContextChip', () => {
     )
 
     expect(screen.getByText('OpenCutSkill')).toBeInTheDocument()
-    expect(screen.getByText('main')).toBeInTheDocument()
     expect(screen.getByText('worktree')).toBeInTheDocument()
-    expect(screen.getByText('desktop-main-54a09f85')).toBeInTheDocument()
+    expect(screen.queryByText('main')).not.toBeInTheDocument()
+    expect(screen.queryByText('desktop-main-54a09f85')).not.toBeInTheDocument()
   })
 
   it('does not show worktree details for a normal checkout', () => {

desktop/src/components/shared/ProjectContextChip.tsx

@@ -26,6 +26,7 @@ export function ProjectContextChip({
   const labelRoot = isWorktree ? (sourceWorkDir || workDir) : workDir
   const label = branch ? (repoName || basename(labelRoot)) : (basename(labelRoot) || repoName || '')
   const worktreeName = worktreeSlug || basename(worktreePath) || 'isolated'
+  const showBranch = !!branch && !isWorktree
   const title = [
     label,
     branch ? `branch: ${branch}` : null,
@@ -43,7 +44,7 @@ export function ProjectContextChip({
         compact ? 'gap-1.5 px-3 py-1.5 text-xs' : 'gap-2 px-4 py-2 text-sm'
       }`}
     >
-      {branch ? (
+      {showBranch ? (
         <svg width={compact ? 15 : 18} height={compact ? 15 : 18} viewBox="0 0 16 16" fill="currentColor" className="shrink-0 text-[var(--color-text-secondary)]">
           <path d="M8 0C3.58 0 0 3.58 0 8c0 3.54 2.29 6.53 5.47 7.59.4.07.55-.17.55-.38 0-.19-.01-.82-.01-1.49-2.01.37-2.53-.49-2.69-.94-.09-.23-.48-.94-.82-1.13-.28-.15-.68-.52-.01-.53.63-.01 1.08.58 1.23.82.72 1.21 1.87.87 2.33.66.07-.52.28-.87.51-1.07-1.78-.2-3.64-.89-3.64-3.95 0-.87.31-1.59.82-2.15-.08-.2-.36-1.02.08-2.12 0 0 .67-.21 2.2.82.64-.18 1.32-.27 2-.27.68 0 1.36.09 2 .27 1.53-1.04 2.2-.82 2.2-.82.44 1.1.16 1.92.08 2.12.51.56.82 1.27.82 2.15 0 3.07-1.87 3.75-3.65 3.95.29.25.54.73.54 1.48 0 1.07-.01 1.93-.01 2.2 0 .21.15.46.55.38A8.013 8.013 0 0016 8c0-4.42-3.58-8-8-8z" />
         </svg>
@@ -51,7 +52,7 @@ export function ProjectContextChip({
         <span className={`material-symbols-outlined text-[var(--color-text-secondary)] ${compact ? 'text-[15px]' : 'text-[18px]'}`}>folder</span>
       )}
       <span className="truncate font-medium text-[var(--color-text-primary)]">{label}</span>
-      {branch ? (
+      {showBranch ? (
         <>
           <span className="text-[var(--color-text-tertiary)]">|</span>
           <span className="truncate">{branch}</span>
@@ -63,7 +64,6 @@ export function ProjectContextChip({
           <span className="shrink-0 rounded-full border border-[var(--color-border)] px-1.5 py-0.5 text-[10px] font-medium uppercase leading-none text-[var(--color-text-tertiary)]">
             worktree
           </span>
-          <span className="max-w-[12rem] truncate">{worktreeName}</span>
         </>
       ) : null}
     </div>

src/server/__tests__/sessions.test.ts

@@ -1990,11 +1990,11 @@ describe('Sessions API', () => {
     }
   })
 
-  it('GET /api/sessions/:id/git-info should include isolated worktree identity', async () => {
+  it('GET /api/sessions/:id/git-info should keep the visible launch branch while including isolated worktree identity', async () => {
     const workDir = await createCleanGitRepo(tmpDir)
     const { sessionId } = await sessionService.createSession(
       workDir,
-      { branch: 'main', worktree: true },
+      { branch: 'feature/rail', worktree: true },
     )
     const launchInfo = await sessionService.getSessionLaunchInfo(sessionId)
     const repository = launchInfo?.repository
@@ -2002,7 +2002,7 @@ describe('Sessions API', () => {
     expect(repository?.worktreeBranch).toBeTruthy()
 
     const activeWorktree = repository!.worktreePath!
-    git(workDir, 'worktree', 'add', '-b', repository!.worktreeBranch!, activeWorktree, 'main')
+    git(workDir, 'worktree', 'add', '-b', repository!.worktreeBranch!, activeWorktree, 'feature/rail')
     const sessionsMap = (conversationService as any).sessions as Map<string, { workDir: string }>
 
     sessionsMap.set(sessionId, { workDir: activeWorktree })
@@ -2022,7 +2022,7 @@ describe('Sessions API', () => {
           branch: string | null
         } | null
       }
-      expect(body.branch).toBe(repository!.worktreeBranch)
+      expect(body.branch).toBe('feature/rail')
       expect(body.workDir).toBe(activeWorktree)
       expect(body.worktree).toEqual({
         enabled: true,
@@ -2067,7 +2067,7 @@ describe('Sessions API', () => {
         branch: string | null
       } | null
     }
-    expect(body.branch).toBe('worktree-desktop-main-12345678')
+    expect(body.branch).toBe('main')
     expect(body.workDir).toBe(activeWorktree)
     expect(body.worktree).toEqual({
       enabled: true,
@@ -2121,7 +2121,7 @@ describe('Sessions API', () => {
         branch: string | null
       } | null
     }
-    expect(body.branch).toBe('worktree-desktop-main-12345678')
+    expect(body.branch).toBe('main')
     expect(body.worktree).toMatchObject({
       path: activeWorktree,
       plannedPath: activeWorktree,

src/server/api/sessions.ts

@@ -670,9 +670,11 @@ async function getGitInfo(sessionId: string): Promise<Response> {
       sameResolvedPath(workDir, worktree.path) ||
       sameResolvedPath(workDir, worktree.plannedPath)
     )
-    const branch = materializedWorktree
+    const branch = sessionBranch || (
-      ? (gitBranch || worktree.branch || sessionBranch)
+      materializedWorktree
-      : (sessionBranch || gitBranch)
+        ? (worktree.branch || gitBranch)
+        : gitBranch
+    )
 
     // Get repo name from remote or directory
     let repoName = ''