feat(research): add research study management functionality

- Implemented models for ResearchStudy, ResearchStudyArm, and ResearchParticipant.
- Created views for listing, creating, updating, and exporting research studies.
- Added bulk participant generation feature with CSV and JSON support.
- Developed templates for study management, participant entry, and bulk generation.
- Introduced URL routing for research study operations.
- Added utility functions for randomisation and participant assignment.
- Implemented participant intake process with demographic data collection.
- Ensured proper handling of participant CIDs and assignment methods.

research/apps.py

@@ -0,0 +1,7 @@
+from django.apps import AppConfig
+
+
+class ResearchConfig(AppConfig):
+    default_auto_field = 'django.db.models.BigAutoField'
+    name = 'research'
+    verbose_name = 'Research Studies'