[Feature] Improve git worktree UX in ZCode Desktop — add worktree switcher and reduce permission prompts

Description

The using-git-worktrees skill has poor UX in the ZCode Desktop app due to two gaps:

1. No worktree switcher in the Desktop UI

There is no UI element (sidebar, dropdown, or command) to list or switch between git worktrees of the current repo. Users must manually open a new folder (File → Open Folder) pointing to the worktree path. This is not discoverable and doesn't feel like first-class worktree support.

Expected: A way to see existing worktrees for the current repo and switch between them from within the app — similar to how VS Code's Git extension shows worktrees in the Source Control view.

2. Manual git worktree fallback triggers excessive permission prompts

When the skill's git fallback path runs, each step triggers a separate sandbox permission prompt:

1. git worktree add .worktrees/feature-x -b feature-x
2. cd .worktrees/feature-x
3. npm install (or equivalent project setup)
4. npm test (baseline verification)

This results in 4+ sequential permission prompts just to set up an isolated workspace. In practice, users either deny the prompts (breaking the workflow) or find the experience too painful to use.

Expected: Batched permissions for the worktree setup flow (e.g., one prompt to authorize the full setup sequence), or a native ZCode worktree tool that handles directory creation, branch setup, and project initialization behind a single approval.

Workaround (for now)

Create the worktree in a terminal and open it as a folder in ZCode Desktop:

cd YourRepo
git worktree add .worktrees/feature-x -b feature-x
# Then: ZCode Desktop → File → Open Folder → .worktrees/feature-x

ZCode detects the existing linked worktree (Step 0 of the skill) and skips creation — zero prompts. But this requires knowing the workaround exists.

Environment

• ZCode Desktop (Windows)
• using-git-worktrees skill v5.1.0
• No native worktree tool available in ZCode platform

Start by reviewing the using-git-worktrees skill v5.1.0 and the Desktop File → Open Folder flow, then reproduce the listed worktree setup commands on Windows to observe the permission prompts. Done should include a discoverable way to list and switch worktrees in the current repository and a single approval for the setup sequence or a native equivalent.