Git worktree manager

GATE: If the task runs inside an existing worktree (a worktree path is given and no create/remove/switch is requested), none of the creation flow applies — work in place and skip this skill. To check: git rev-parse --show-toplevel appears as a linked entry in git worktree list.

Working rules

• Work in place when given an existing worktree without a creation/removal request.
• Keep one writer per worktree and preserve other sessions' branches, files, and staged work.
• Verify dependencies resolve first-party code from the intended worktree.
• Keep merge, push, and cleanup within user authorization; report the exact exercised checkout and resulting commit.

Always use the manager script

Never call git worktree add directly -- always use the worktree-manager.sh script.