feat: prefix the css class names

[Benehiko]

This PR simplifies class overrides by providing a prefix name for the generated CSS classes.

In this case we add a prefix ory_elements__ to each class name.

The format is as follows: ory_elements_<variant|size>__hash

Example generated classes: ory_elements__button_social__i8n2ik0 ory_elements__button_social_size_medium__ecxsa2d ory_elements__button_social_variant_semibold__xas31dg

See this discussion for more details https://github.com/ory/elements/discussions/162

Related Issue or Design Document

Checklist

• [ ] I have read the contributing guidelines and signed the CLA.
• [ ] I have referenced an issue containing the design document if my change introduces a new feature.
• [ ] I have read the security policy.
• [ ] I confirm that this pull request does not address a security vulnerability. If this pull request addresses a security vulnerability, I confirm that I got approval (please contact security@ory.sh) from the maintainers to push the changes.
• [ ] I have added tests that prove my fix is effective or that my feature works.
• [ ] I have added the necessary documentation within the code base (if appropriate).

Further comments

[Benehiko]

Without the hash doesn't work.

even playwright tests are failing since the UI elements aren't rendering properly. I'll add the hash back.