fix: enhance notifications and validation features

- Added URL validation for notification providers to ensure only valid http/https URLs are accepted.
- Implemented tests for URL validation scenarios in the Notifications component.
- Updated translations for error messages related to invalid URLs in multiple languages.
- Introduced new hooks for managing security headers and access lists in tests.
- Enhanced the ProviderForm component to reset state correctly when switching between add and edit modes.
- Improved user feedback with update indicators after saving changes to notification providers.
- Added mock implementations for new hooks in various test files to ensure consistent testing behavior.

frontend/src/components/__tests__/SecurityNotificationSettingsModal.test.tsx

@@ -154,11 +154,10 @@ describe('SecurityNotificationSettingsModal', () => {
     renderModal();
 
     await waitFor(() => {
-      expect(screen.getByLabelText('Enable Notifications')).toBeTruthy();
+      expect(screen.getByLabelText('Enable Notifications')).toBeChecked();
     });
 
     const enableSwitch = screen.getByLabelText('Enable Notifications') as HTMLInputElement;
-    expect(enableSwitch.checked).toBe(true);
 
     // Disable notifications
     await user.click(enableSwitch);