feat: Integrate Nostr chat preloader for improved chat data handling

- Introduce a new composable, useNostrChatPreloader, to manage chat data preloading, including peer loading and subscription for notifications.
- Update ChatComponent to utilize the preloader, ensuring chat data is ready before connecting.
- Enhance Navbar to display unread message counts with notification badges for better user experience.
- Refactor App.vue to trigger both market and chat preloading upon successful login, streamlining the user experience.

src/App.vue

@@ -8,13 +8,15 @@ import { Toaster } from '@/components/ui/sonner'
 import 'vue-sonner/style.css'
 import { auth } from '@/composables/useAuth'
 import { useMarketPreloader } from '@/composables/useMarketPreloader'
+import { useNostrChatPreloader } from '@/composables/useNostrChatPreloader'
 import { toast } from 'vue-sonner'
 
 const route = useRoute()
 const showLoginDialog = ref(false)
 
-// Initialize market preloader
+// Initialize preloaders
 const marketPreloader = useMarketPreloader()
+const chatPreloader = useNostrChatPreloader()
 
 // Hide navbar on login page
 const showNavbar = computed(() => {
@@ -25,8 +27,9 @@ function handleLoginSuccess() {
   showLoginDialog.value = false
   toast.success('Welcome back!')
   
-  // Trigger market preloading after successful login
+  // Trigger preloading after successful login
   marketPreloader.preloadMarket()
+  chatPreloader.preloadChat()
 }
 
 onMounted(async () => {
@@ -38,11 +41,17 @@ onMounted(async () => {
   }
 })
 
-// Watch for authentication changes and trigger market preloading
+// Watch for authentication changes and trigger preloading
 watch(() => auth.isAuthenticated.value, (isAuthenticated) => {
-  if (isAuthenticated && !marketPreloader.isPreloaded.value) {
-    console.log('User authenticated, triggering market preload...')
-    marketPreloader.preloadMarket()
+  if (isAuthenticated) {
+    if (!marketPreloader.isPreloaded.value) {
+      console.log('User authenticated, triggering market preload...')
+      marketPreloader.preloadMarket()
+    }
+    if (!chatPreloader.isPreloaded.value) {
+      console.log('User authenticated, triggering chat preload...')
+      chatPreloader.preloadChat()
+    }
   }
 }, { immediate: true })
 </script>