Crash when applying swatch to stroke
#### Summary
Inkscape crashes when applying a document swatch to the stroke of selected shapes, using the "palette" panel.
#### Steps to reproduce:
- open Inkscape
- open the provided sample file
- select rectangle
- shift click the document swatch from the swatches panel
#### What happened?
- Inkscape crashes
#### What should have happened?
- The selected swatch should have been applied to the shape stroke
#### Sample attachments:
Screen recording
{width=800 height=500}
Sample svg file
{width=329 height=600}
#### Version info
Inkscape 1.5-dev (81a8d32, 2025-12-07)
Compile (Run)
GLib version: 2.83.4
GTK version: 4.20.2 (4.20.2)
glibmm version: 2.83.1
gtkmm version: 4.20.0
libxml2 version: 2.11.5
libxslt version: 1.1.35
Cairo version: 1.18.2 (1.18.2)
Pango version: 1.56.1 (1.56.1)
HarfBuzz version: 10.2.0 (10.2.0)
Poppler version: 24.02.0
OS version: macOS 15.5 (24F74) arm64
issue