refactor: improve nostr connection and message handling

- Add WebSocket manager class for better connection handling
- Split message handling into separate store
- Add encryption service class
- Create chat composable for reusable chat logic
- Add error handling service
- Add connection status indicators throughout app
- Add message persistence service
- Improve subscription reliability with EOSE handling
- Add connection state management
- Hide status text on mobile for better space usage

These changes improve code organization, reliability, and user experience by:
- Better separation of concerns
- More robust error handling
- Clearer connection status feedback
- Improved message persistence
- More maintainable WebSocket management
- Better mobile responsiveness

Breaking changes:
- Message handling moved to separate store
- WebSocket connections now managed through NostrWebSocketManager
- Encryption now handled through NostrEncryption service

src/components/layout/Navbar.vue

@@ -9,6 +9,7 @@ import { useRouter } from 'vue-router'
 import LogoutDialog from '@/components/ui/logout-dialog/LogoutDialog.vue'
 import Login from '@/components/Login.vue'
 import { Dialog, DialogContent } from '@/components/ui/dialog'
+import ConnectionStatus from '@/components/ConnectionStatus.vue'
 
 const { t, locale } = useI18n()
 const { theme, setTheme } = useTheme()
@@ -84,6 +85,8 @@ const openLogin = () => {
           {{ locale === 'en' ? '🇪🇸 ES' : '🇺🇸 EN' }}
         </Button>
 
+        <ConnectionStatus v-if="nostrStore.isLoggedIn" />
+
         <template v-if="nostrStore.isLoggedIn">
           <LogoutDialog :onLogout="handleLogout" />
         </template>