Extract message list into dedicated MessageListView (#1080)

* Extract message list into dedicated MessageListView

* Fix broken smoke test

Mounts two distinct fixtures to cover separate render branches: a truncatable message (>2000 chars, no payment tokens) and a payment message (lightning + cashu, private, partial delivery). Expectations guard that each fixture actually reaches its intended branch.

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Co-authored-by: jack <212554440+jackjackbits@users.noreply.github.com>

bitchat/ViewModels/ChatViewModel.swift

@@ -1799,7 +1799,15 @@ final class ChatViewModel: ObservableObject, BitchatDelegate, CommandContextProv
             }
         }
     }
-    
+
+    func getMessages(for peerID: PeerID?) -> [BitchatMessage] {
+        if let peerID {
+            return getPrivateChatMessages(for: peerID)
+        } else {
+            return messages
+        }
+    }
+
     @MainActor
     func getPrivateChatMessages(for peerID: PeerID) -> [BitchatMessage] {
         var combined: [BitchatMessage] = []