Dock: unable to unpin items

### Microsoft PowerToys version

0.100.0

### Installation method

PowerToys auto-update

### Area(s) with issue?

Command Palette

### Steps to reproduce

1. Pin the clipboard history to the dock
2. Right click on its icon in the dock -> No button to unpin. Clicking the button to pin it does nothing.
3. Bring up CmdPal, search for clipboard history, bring up context menu with Ctrl+k or right-click -> same result as step 2.

This is the same for all items I pined to the dock. Only winget (which is pinned by default) can be unpinned.

### ✔️ Expected Behavior

Items can be unpinned

### ❌ Actual Behavior

Items cannot be unpinned

### Upload Bug Report ZIP-file

_No response_

### Additional Information

Windows 11 Pro 25H2

### Other Software

_No response_

Start by reproducing the issue in Command Palette: pin Clipboard History to the dock, then inspect the right-click and Ctrl+K context menus from both the dock and search results. Done means every user-pinned item, not only winget, exposes a working unpin action.

Written by the indexing model from the issue text.