Fix Build Errors (Clean up ChatComponent and useNostrChat)

- Remove unused ChatMessage interface from ChatComponent to streamline
the code.
- Update getPeerAvatar function parameter for clarity by renaming it to
_peer.
- Remove unnecessary useNostrStore import in useNostrChat, simplifying
the composable's structure.

src/components/nostr/ChatComponent.vue

@@ -290,12 +290,7 @@ interface Peer {
   pubkey: string
 }
 
-interface ChatMessage {
-  id: string
-  content: string
-  created_at: number
-  sent: boolean
-}
+
 
 // State
 const peers = ref<Peer[]>([])
@@ -454,7 +449,7 @@ const formatTime = (timestamp: number) => {
   })
 }
 
-const getPeerAvatar = (peer: Peer) => {
+const getPeerAvatar = (_peer: Peer) => {
   // You can implement avatar logic here
   return null
 }