feat(doctor): add doctor dashboard views for assigned queue, waiting queue, and medicine availability

What does this MR do and why?

This MR adds a dedicated doctor workflow starting from the dashboard through queue management and medicine availability.

Earlier, doctor users did not have a clear, end-to-end experience to view their assigned patients, monitor the waiting queue, or quickly check medicine availability. This change introduces doctor-focused navigation and pages to make their day-to-day camp workflow smoother and more reliable.

In addition, queue data could sometimes include duplicates or records from different camps. This MR improves correctness by adding camp-aware filtering and deduplication.

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Changes included

• Added doctor role support in the Dashboard and AppLayout navigation.
• Introduced new doctor routes:
  • /doctor
  • /doctor/assigned-queue
  • /doctor/waiting-queue
  • /doctor/medicine-availability
• Added DoctorHomePage with quick action cards for common doctor tasks.
• Added DoctorPage with three main views:
  • Assigned queue
  • Waiting queue
  • Medicine availability (with search)
• Implemented queue deduplication by book_no with proper priority and status handling.
• Added live waiting-time display and improved socket error visibility.
• Introduced getLatestMedicalCamp() helper and scoped doctor queue data to the active camp.
• Extended the QueuePatient type with optional camp_id and camp_date for camp-aware filtering.

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Why this change

• Doctors previously lacked a dedicated, streamlined workflow.
• Queue data could include duplicates or mixed-camp records.
• Improves usability, correctness, and role-based navigation clarity.
• Lays groundwork for future doctor-specific enhancements.

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Screenshots or screen recordings

before:blank page

after: ---#164 (closed)