AI Assistant tab icons are poorly visible in the "Light" editor theme

Steps to reproduce:

1. Create a new Unity Project
2. Go to Unity ->Settings ->General
3. Set Editor Theme to "Light"
4. Install the AI Assistant package via Package Manager (com.unity.ai.assistant)
5. Navigate to Window > AI > Assistant
6. Observe the "Assistant" tab

Actual results: The icons, displayed in front of the title, are poorly visible.

Expected results: The icons should be dark grey, and they should be more visible.

Reproducible with versions: 1.0.0-pre.10(6000.3.0a3)

Not reproducible with versions: -

Can’t test with versions: -

Tested on (OS): M1 Max - Sequoia 15.5