Refactor Experiment and Phase components for improved state management and UI consistency

- Resolved merge conflicts and cleaned up code in ExperimentForm, enhancing initial state handling and validation logic.
- Updated PhaseForm to reflect correct placeholder text for descriptions.
- Simplified Sidebar component by removing unused props and ensuring consistent behavior across expanded and collapsed states.
- Adjusted Scheduling component to streamline repetition management and improve user experience.

management-dashboard-web-app/src/components/PhaseForm.tsx

@@ -147,11 +147,7 @@ export function PhaseForm({ onSubmit, onCancel, loading = false }: PhaseFormProp
                     onChange={(e) => handleInputChange('description', e.target.value)}
                     rows={3}
                     className="w-full px-3 py-2 border border-gray-300 rounded-md shadow-sm focus:outline-none focus:ring-2 focus:ring-blue-500 focus:border-blue-500"
-<<<<<<< HEAD
-                    placeholder="Optional description of this experiment phase"
-=======
                     placeholder="Optional description of this experiment book"
->>>>>>> old-github/main
                     disabled={loading}
                 />
             </div>