fic doctor mogin/logout buttons in manage doctor

Title: Include Doctor Login/Logout Status in /doctors API

Description: The frontend requires login_time and logout_time for each doctor to correctly determine availability and button states. Previously, this data was not included in the /doctors API, causing UI inconsistencies.

Problem:

• /doctors API did not include attendance data
• Frontend could not determine login state after refresh
• Required temporary frontend cache hacks

Solution Implemented:

• Fetch CampVisit records for active medical camp
• Filter by CampRoleEnum.doctor
• Map visits using user_id to avoid N+1 queries
• Attach login_time and logout_time to each doctor in response

Tasks:

1. Ensure /doctors API returns:

   • login_time
   • logout_time

2. Fetch only latest visit per doctor for active camp

3. Optimize query to avoid N+1 issues (use mapping/dictionary)

4. Maintain clean schema compatibility with frontend

5. Handle edge cases:

   • No visit → both fields null
   • Multiple visits → return latest

Expected Response Example: { "id": "doctor_id", "doctor_name": "Dr. X", "login_time": "timestamp | null", "logout_time": "timestamp | null" }

Acceptance Criteria:

• API returns correct attendance data for each doctor
• Works efficiently (no N+1 queries)
• Frontend reflects correct state after refresh
• Supports active camp filtering

Priority: High