Add RichText

**Is your feature request related to a problem? Please describe.**
I'm always frustrated when it doesn’t allow me for RichText

**Describe the solution you'd like**
add RichText support

The issue requests RichText support but does not specify what that entails. Look at the existing text animation widgets in the package to understand the current architecture. Determine what RichText features are missing and how they would integrate with the animation system. Check if there are any related discussions or PRs in the repository history.

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