`public` `DefaultInterpolatedStringHandler` polyfill causes error.

[akeit0]

Describe the bug
DefaultInterpolatedStringHandler polyfill implementations is marked as public, which causes conflicts when we already have own polyfills or use other packages with similar polyfills.
To Reproduce
Steps to reproduce the behavior:

1. Install this package in a project that already has polyfilled DefaultInterpolatedStringHandler.
2. Try to use both the existing polyfills and this package
3. Observe naming conflicts and compilation errors

Expected behavior

Logs

Additional context