v0.12.0 - Add modular system architecture with user-based module access

- Add Modules and UserModules database tables
- Create home page with module selection grid
- Implement per-user module assignment in user management
- Add route guards for module access control
- Refactor navigation: login -> home -> modules, admin console via button
- Add Font Awesome icons

templates/create_session.html

@@ -34,7 +34,7 @@
             </div>
 
             <div class="form-actions">
-                <a href="{{ url_for('dashboard') }}" class="btn btn-secondary">Cancel</a>
+                <a href="{{ url_for('admin_dashboard') }}" class="btn btn-secondary">Cancel</a>
                 <button type="submit" class="btn btn-primary">Create Session</button>
             </div>
         </form>