135b63e067
When creating a worktree from a remote-tracking ref (e.g. origin/feature/foo), git automatically sets the new branch's upstream to that ref. This caused new task branches to incorrectly track the original remote branch instead of starting with no upstream. Add -c branch.autoSetupMerge=false to gitAddWorktree and gitAddWorktreeWithGitCrypt. The explicit CheckoutBranch flow (PR reviews) is unaffected — it sets upstream via setUpstreamIfExists after creation.