Bug: Merge button missing from worktree actions dropdown

The backend merge endpoint and frontend handler both exist, but no UI element exposes this functionality. Users cannot merge their feature branch into main from within Automaker.

Environment

• Automaker: current main branch (commit 05f1d8e0)
• Applies to all platforms

Evidence

Backend exists:

• POST /api/worktree/merge endpoint in apps/server/src/routes/worktree/routes/merge.ts

Frontend handler exists:

• handleMergeFeature() function in apps/ui/src/components/views/board-view/hooks/use-board-actions.ts (line 711)
• Handler is extracted in board-view.tsx (line 413) but never passed to any UI component

UI is missing:

• Worktree dropdown (apps/ui/src/components/views/board-view/worktree-panel/components/worktree-actions-dropdown.tsx) has these actions:
  • Dev Server, Pull, Push, Pull & Resolve Conflicts, Commit, Create PR, Address PR Comments, Open in Editor, Delete Worktree
  • No Merge option

Expected Behavior

The worktree actions dropdown should include a "Merge" button that triggers handleMergeFeature() to merge the feature branch into main.

Actual Behavior

Users must either:

1. Create a PR and merge externally on GitHub
2. Use git CLI manually to merge

Related Issues

• [Bug]: Completing worktree features doesn't warn about or require merging unmerged branches #407 - Completing worktree features doesn't warn about or require merging unmerged branches (related but different - that issue is about warnings at completion time, this issue is about the missing UI control to perform merges)

Notes

• "Pull & Resolve Conflicts" merges main INTO your branch (opposite direction), which is not the same as merging your feature branch into main