Add pagination support to FHIRGateway.search method

[RakinduM]

Description

Added pagination support to the FHIR search operations with comprehensive test coverage. This implements standard FHIR pagination using Bundle links and allows for automatic fetching of multiple pages with configurable limits.

Related Issue

#129

Changes Made

• Added pagination parameters (follow_pagination and max_pages) to search methods
• Implemented pagination logic following FHIR Bundle.link specifications
• Added tests for pagination functionality

Testing

Added the following test cases in test_fhir.gateway.py:

• test_search_with_pagination: Verifies multi-page result fetching
• test_search_with_max_pages: Tests page limit enforcement
• test_search_with_pagination_empty_next_link: Validates handling of bundles without next links
• test_search_with_pagination_and_provenance: Tests integration with provenance metadata

Checklist

• I have read the contributing guidelines
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• My changes generate no new warnings
• I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes

[RakinduM]

Hi @jenniferjiangkells, If it is possible, could you add the Hacktoberfest-Accepted label ?

[jenniferjiangkells]

Hi @RakinduM thanks for this - looks good to me. I have linked it to the issue which is tagged with hacktoberfest :)

[RakinduM]

Hi @jenniferjiangkells, Glad to hear that! I spent some good time on this and really enjoyed working on it :).
Thanks for linking it to the issue and tagging Hacktoberfest!