docs: add comprehensive static daily reminders documentation

- Add static daily reminders to README.md core features and API reference
- Create detailed usage guide in USAGE.md with examples and best practices
- Add version 2.1.0 changelog entry documenting new reminder functionality
- Create examples/static-daily-reminders.ts with complete usage examples
- Update test-apps README to include reminder testing capabilities

The static daily reminder feature provides simple daily notifications
without network content dependency, supporting cross-platform scheduling
with rich customization options.

USAGE.md

@@ -39,6 +39,71 @@ await DailyNotification.scheduleDailyNotification({
 - **`enableErrorHandling`**: Advanced retry logic with exponential backoff
 - **`enablePerformanceOptimization`**: Database indexes, memory management, object pooling
 
+## Static Daily Reminders
+
+For simple daily reminders that don't require network content or content caching:
+
+### Basic Usage
+
+```typescript
+// Schedule a simple daily reminder
+await DailyNotification.scheduleDailyReminder({
+  id: 'morning_checkin',
+  title: 'Good Morning!',
+  body: 'Time to check your TimeSafari community updates',
+  time: '09:00'  // HH:mm format
+});
+```
+
+### Advanced Configuration
+
+```typescript
+// Schedule a customized reminder
+await DailyNotification.scheduleDailyReminder({
+  id: 'evening_reflection',
+  title: 'Evening Reflection',
+  body: 'Take a moment to reflect on your day',
+  time: '20:00',
+  sound: true,
+  vibration: true,
+  priority: 'high',
+  repeatDaily: true,
+  timezone: 'America/New_York'
+});
+```
+
+### Reminder Management
+
+```typescript
+// Get all scheduled reminders
+const result = await DailyNotification.getScheduledReminders();
+console.log('Scheduled reminders:', result.reminders);
+
+// Update an existing reminder
+await DailyNotification.updateDailyReminder('morning_checkin', {
+  title: 'Updated Morning Check-in',
+  time: '08:30',
+  priority: 'high'
+});
+
+// Cancel a specific reminder
+await DailyNotification.cancelDailyReminder('evening_reflection');
+```
+
+### Key Benefits
+
+- ✅ **No Network Required**: Works completely offline
+- ✅ **No Content Cache**: Direct notification display without caching
+- ✅ **Simple API**: Easy-to-use methods for basic reminder functionality
+- ✅ **Persistent**: Survives app restarts and device reboots
+- ✅ **Cross-Platform**: Consistent behavior across Android, iOS, and Web
+
+### Time Format
+
+Use 24-hour format with leading zeros:
+- ✅ Valid: `"09:00"`, `"12:30"`, `"23:59"`
+- ❌ Invalid: `"9:00"`, `"24:00"`, `"12:60"`
+
 ## Platform-Specific Features
 
 ### Android