Make TyperAnimatedText selectable

**Describe the bug**
Make TyperAnimatedText selectable, becoz in case if i need to select that text on top , i cant select and copy the text.
Or PLease let me know if we can do that already and i am missing something.

Look for the TyperAnimatedText widget in the codebase, likely in lib/src/. Check its build method to see how it renders text, and ensure the Text widget has SelectableText or the selectable property. Review similar animated text widgets for patterns. Test the change in an example app to verify text can be selected and copied.

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