Sketcher: Scale default shortcut (Z, P, S) conflicts with Rotate / Polar Transform (Z, P)

### Problem description

The default keyboard shortcut for Scale in the Sketcher is unusable as it competes with the shortcut assigned to Rotate / Polar Transform.

### Workbench affected?

Sketcher

### Steps to reproduce

1. Open or create a sketch.
2. Draw a rectangle.
3. Select the rectangle.
4. Press Z, then press P.
5. Rotate / Polar Transform is invoked and the full sequence Z, P, S cannot be completed for Scale.

### Expected behavior

The Scale tool in the Sketcher should not have a keyboard shortcut that conflicts with Rotate / Polar Transform.

### Actual behavior

Z, P invokes Rotate / Polar Transform and Scale cannot be used.

### Development version About Info (in Safe Mode)

```shell
OS: Arch Linux (niri/wayland)
Architecture: x86_64
Version: 1.1.3.44987 (Git)
Build date: 2026/07/25 04:52:02
Build type: Release
Branch: makepkg
Hash: 145529fe741292ff0b3977a01195bf0247425794
Python 3.14.7, Qt 6.11.1, Coin 4.0.10, Vtk 9.6.2, boost 1_92, Eigen3 5.0.1, PySide 6.11.1
shiboken 6.11.1, SMESH 7.7.1.0, xerces-c 3.3.0, OCC 7.9.3
Locale: English/Singapore (en_SG)
Navigation Style/Orbit Style/Rotation Mode: CAD/Rounded Arcball/Window center
Stylesheet/Theme/QtStyle: FreeCAD.qss/FreeCAD Light/
Logical DPI/Physical DPI/Pixel Ratio: 96/123.535/2
```

### Last known good version (optional)

```shell

```

Reproduce the conflict in a FreeCAD Sketcher workbench by selecting a rectangle and entering Z, P, then inspect how the Scale and Rotate / Polar Transform shortcuts are defined. Done means Scale has a usable non-conflicting default shortcut while Rotate / Polar Transform still works, and the reported sequence can be verified again.

Written by the indexing model from the issue text.