Cleanup --all should use canonical path from git

[wollax]

Problem

handle_worktree_cleanup_all computes worktree path as worktree_dir.join(&entry.spec_slug), then falls back to entry.path if the computed path doesn't exist. This heuristic can silently use a stale entry.path from git worktree list that may differ from what the user expects based on --worktree-dir.

Solution

Solution

Always use entry.path (the canonical path from git) for cleanup operations, since git worktree list already returns the actual path.

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Created via Kata PR review backlog