refactor(database): migrate to new modular database layer and unify data access

- Remove legacy database.ts, LocalDataSource.ts, and MessageRepository.ts
- Create new src/database/ module with messageRepository, userCacheRepository, conversationRepository, and groupCacheRepository
- Update all consumers to import from @/database instead of services/database
- Add web platform blur handling for modal components to fix focus issues
- Flatten SystemMessageItem and NotificationsScreen styles for consistent design
- Add draggable slider in ChatSettingsScreen and dynamic font size support
- Introduce 9 new chat color themes
- Add profile screens for about, terms, and privacy policy with navigation routes
- Add policy links to login and registration screens
- Fix post share URL format from /posts/ to /post/

src/components/call/IncomingCallModal.tsx

@@ -9,6 +9,7 @@ import {
   Modal,
   StatusBar,
   Dimensions,
+  Platform,
 } from 'react-native';
 import { MaterialCommunityIcons } from '@expo/vector-icons';
 import { callStore } from '../../stores/callStore';
@@ -25,6 +26,10 @@ const IncomingCallModal: React.FC = () => {
 
   useEffect(() => {
     if (incomingCall) {
+      if (Platform.OS === 'web') {
+        const active = (globalThis as any)?.document?.activeElement as { blur?: () => void } | undefined;
+        active?.blur?.();
+      }
       const pulse = Animated.loop(
         Animated.sequence([
           Animated.timing(pulseAnim, {