Move Session route for Nuxt Auth Utils to /.nuxt-auth-utils/session to avoid polluting /api namespace

[victorfds]

This PR addresses issue #389 by refactoring Nuxt Auth Utils to move the session endpoint from the /api namespace to /.nuxt-auth-utils/session. This change prevents pollution of the /api namespace, improving the project's routing structure and avoiding potential conflicts with user-defined API routes.

Changes

• Updated session route to use /.nuxt-auth-utils/session instead of /api.
• Ensured backward compatibility where applicable.
• All existing tests are passing, confirming the refactor does not introduce regressions.
• No additional dependencies were added.

Testing

• Ran all unit and integration tests locally, and they are passing.
• Manually tested the new session endpoint to ensure functionality remains intact.
• Verified that the /api namespace is no longer used by Nuxt Auth Utils.

Additional Notes

• Please let me know if additional test cases or documentation updates are needed.