refactor: Consolidate settings page save buttons for better UX

Improved the settings page by removing individual save buttons from each
preference component and adding unified save buttons per section:

## Changes Made

### Component Updates
- **TimeZoneSelector**: Converted to controlled component with value/onChange props
  * Removed internal state management and save button
  * Removed success/error alerts (now handled by parent)
  * Added auto-detect as simple button without save

- **TimeFormatSelector**: Converted to controlled component with value/onChange props
  * Removed internal state management and save button
  * Removed success/error alerts (now handled by parent)
  * Simplified to just radio buttons with preview

### Settings Page Improvements
- Added timezone and timeFormat to local state
- Created separate save handlers:
  * `handleSaveProfile` - for name/email changes
  * `handleSavePreferences` - for timezone and time format
- Three clear sections with dedicated save buttons:
  1. **Profile Information** → "Save Profile" button
  2. **Preferences** (Language, Units, Timezone, Time Format) → "Save Preferences" button
  3. **Notifications** → "Save Notification Settings" button

### User Experience Benefits
- Clearer separation between different types of settings
- Single save action per logical section instead of multiple buttons
- Consistent save pattern across all settings cards
- Reduced visual clutter with fewer buttons on page
- Better organization: related settings grouped with one save action

Files changed: 3 files (TimeZoneSelector, TimeFormatSelector, settings page)

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

docs/LOCALIZATION_IMPLEMENTATION_PLAN.md

@@ -54,6 +54,7 @@ Implement comprehensive internationalization (i18n) support for the Maternal App
 - Individual tracking pages (feeding, sleep, diaper, medicine) with unit conversions (Phase 12)
 - Family management page localization
 - Analytics/insights page localization
+- Settings page localization
 - Date/time localization throughout app (Phase 10)
 - Number formatting per locale (Phase 11)
 - Professional translation review (Phase 13.2)