Pull Request Template

Description

• Fix the material not being refreshed when shadowMode changes at runtime between None and an enabled mode such as Outline.
• Replace the duplicated SetVerticesDirty() call in the shadowMode setter with SetMaterialDirty().
• This reevaluates the CanvasRenderer material and propagates the material refresh to TMP submesh replicas.

Type of change

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Update documentations
• Others (refactoring, style changes, etc.)

Test environment

• Platform: Editor (Windows), Standalone (Windows)
• Unity version: 6000.3.20f1
• Build options: Built-in Render Pipeline, StandaloneWindows64
• Validation:
  • All 6 EditMode tests passed, including local regression coverage for dirty callbacks, CanvasRenderer material, and TMP main/submesh material transitions.
  • StandaloneWindows64 player build succeeded.

Checklist

• This pull request is for merging into the develop branch
• My code follows the style guidelines of this project
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• My changes generate no new warnings
• I have checked my code and corrected any misspellings