[Frontend] Implement 'get_active_pools_paginated'

[Akshola00]

Description
Frontend dashboards displaying "Explore New Scholarships" require similar slicing mechanisms representing the Pools lists.

Explicit Expectations

• Build get_active_pools_paginated extracting arrays iteratively bounding pool_id lookups.
• Filter instances returning only where pool.is_active == true.

Acceptance Criteria

• Frontend SDKs integrate efficiently off loading limits.

Contributor checklist:

• Ensure the project builds successfully.
• Add or update tests for all new/changed logic.
• Make sure all tests pass.
• Run the formatter / linter so code is properly formatted and consistent.