Refactor user authentication and dashboard features

- Added `is_admin` field to User model for role management.
- Updated user context middleware to include current user in templates.
- Enhanced session management with improved debug middleware.
- Refactored dashboard view to fetch user-specific data and recent events.
- Improved login and registration templates for better user experience.
- Added admin routes with access control for admin users.
- Updated Docker configuration for better error logging and dependency management.
- Updated requirements to include new dependencies and specify versions.

app/templates/team_detail.html

@@ -64,7 +64,7 @@
         <div class="flex items-center justify-between">
           <div class="flex items-center">
             <div class="w-10 h-10 rounded-full bg-gray-200 mr-3 overflow-hidden">
-              <img src="https://via.placeholder.com/40" alt="User" class="w-full h-full object-cover">
+              <img src="https://picsum.photos/40" alt="User" class="w-full h-full object-cover">
             </div>
             <div>
               <p class="font-medium">{{ member.user.username }}</p>