fix: added optional medicalcamp_id in analytics and doctors/registered

Title (semantic)

feat(analytics): add optional medical_camp_id query param to analytics and doctors-registered endpoints

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Description

This merge request introduces support for an optional medical_camp_id query parameter across analytics and doctors-registered endpoints. The goal is to allow flexible reporting and historical data access while maintaining backward compatibility with existing behavior.

Backend Changes

• Updated endpoints to accept medical_camp_id as an optional query parameter:
  • GET /api/v1/analytics
  • GET /api/v1/analytics/medicines
  • GET /api/v1/analytics/doctors
  • GET /api/v1/doctors/registered
• Implemented dynamic medical camp resolution:
  • If medical_camp_id is provided → data is scoped to that camp.
  • If omitted → system defaults to the latest medical camp.
• Ensured endpoints rely only on query params (no GET request bodies).
• Refactored service layer logic to support camp-based filtering.
• Added validation for invalid or non-existent camp IDs.

Testing & Documentation

• Added unit tests covering:
  • Requests with medical_camp_id
  • Requests without parameter (latest camp fallback)
  • Invalid camp handling
• Updated API docs to include new optional query parameter.

This enhancement improves analytics flexibility and enables querying historical camp data without introducing new endpoints.

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Checklist

• Optional query param added to supported endpoints
  • Default latest camp fallback implemented
  • Service layer updated for dynamic camp resolution
  • Unit tests added and passing
  • API documentation updated

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Related Issue(s)

Closes #36 (closed)