Monomer and presets previews have small white angles on the border

[svvald]

Steps to Reproduce

1. Create any presets/monomers sequence in macromolecules mode
2. Hover over any monomer in flex/snake mode or preset/linker node in sequence mode

Actual behavior Preview for monomer or preset appears and it has small angles by the radial grey border.

Expected behavior Previews shouldn't have white angles, border should be radial without any artifacts.

Screenshots

If applicable, add screenshots to help explain your problem.

Desktop (please complete the following information):

• OS: macOS Sequoia 15.0
• Browser: Chrome
• Version: 130.0.6723.59 (Official Build) (x86_64)

Ketcher version [Version 2.26.0-rc.1] Indigo version [Version 1.25.0-rc.3]