Add forms for profile and password settings; improve tests for settings pages

- Implement `ProfileSettingsForm` and `PasswordChangeForm` components to manage user profile and password updates.
- Add `SessionCard` for session management and related API hooks (`useSession`).
- Update settings page tests to include user state mock and React Query provider for better test reliability.
- Enhance `PasswordSettingsPage` and `ProfileSettingsPage` tests to verify component rendering and user interaction.
- Improve API hook structure with dedicated hooks for session and user profile management.

frontend/src/components/settings/index.ts

@@ -1,4 +1,7 @@
 // User settings components
 // Examples: ProfileSettings, SessionList, PasswordChangeForm, etc.
 
-export {};
+export { ProfileSettingsForm } from './ProfileSettingsForm';
+export { PasswordChangeForm } from './PasswordChangeForm';
+export { SessionCard } from './SessionCard';
+export { SessionsManager } from './SessionsManager';