feat: Add paginated iteration and Ruby 3 ActiveAdmin compatibility

[aundurraga]

Summary

Adds paginated iteration support to BudaActiveResource::Base and improves ActiveAdmin query compatibility across Ruby versions.

• Adds FIND_PER_PAGE, find_each, and retry_on_error to support batch-style iteration over remote ActiveResource collections.
• Updates process_active_admin_collection_query to accept both positional option hashes and keyword arguments, supporting Ruby 2.7 and Ruby 3+ call behavior.