Pie chart text unreadable in dark mode due to missing theme color variable #187

While using the library in dark mode, the legend and title text in the pie chart section become unreadable. The light theme displays correctly, but the dark theme does not adjust text colors properly.

Steps to Reproduce:

1. Enable dark mode in the app or system settings.
2. Render a pie chart using the library.
3. Observe the legend and title text color.

Expected Behavior:

Text for legends and titles in the pie chart should be clearly visible in both light and dark themes.

Actual Behavior:
In dark mode, the text color in the pie chart does not adapt, making it hard to read against the dark background.

Proposed Solution:
Introduce separate color variables for both legend text and title text in the color file, and reference them in the theme configuration. These variables should update automatically based on the selected theme mode (light or dark).

Additional Information:
A screenshot of the dark mode issue in the pie chart section is attached for reference.