feat: enhance project and scenario management with role-based access control

- Implemented role-based access control for project and scenario routes.
- Added authorization checks to ensure users have appropriate roles for viewing and managing projects and scenarios.
- Introduced utility functions for ensuring project and scenario access based on user roles.
- Refactored project and scenario routes to utilize new authorization helpers.
- Created initial data seeding script to set up default roles and an admin user.
- Added tests for authorization helpers and initial data seeding functionality.
- Updated exception handling to include authorization errors.

services/exceptions.py

@@ -12,6 +12,10 @@ class EntityConflictError(Exception):
     """Raised when attempting to create or update an entity that violates uniqueness."""
 
 
+class AuthorizationError(Exception):
+    """Raised when a user lacks permission to perform an action."""
+
+
 @dataclass(eq=False)
 class ScenarioValidationError(Exception):
     """Raised when scenarios fail comparison validation rules."""