Fix URL detection and message spacing

- Add URL detection to message formatting with blue color and underline
- Replace List with ScrollView for precise spacing control
- Use minimal vertical padding (1px) between messages
- Remove LazyLinkPreviewView, use LinkPreviewView directly
- URLs now appear highlighted in message text AND show preview below

bitchat/Views/ContentView.swift

@@ -163,21 +163,22 @@ struct ContentView: View {
     
     private func messagesView(privatePeer: String?) -> some View {
         ScrollViewReader { proxy in
-            List {
-                let messages: [BitchatMessage] = {
-                    if let privatePeer = privatePeer {
-                        let msgs = viewModel.getPrivateChatMessages(for: privatePeer)
-                        return msgs
-                    } else {
-                        return viewModel.messages
-                    }
-                }()
-                
-                // Implement windowing - show last 100 messages for performance
-                let windowedMessages = messages.suffix(100)
-                
-                ForEach(Array(windowedMessages), id: \.id) { message in
-                        VStack(alignment: .leading, spacing: 2) {
+            ScrollView {
+                VStack(alignment: .leading, spacing: 0) {
+                    let messages: [BitchatMessage] = {
+                        if let privatePeer = privatePeer {
+                            let msgs = viewModel.getPrivateChatMessages(for: privatePeer)
+                            return msgs
+                        } else {
+                            return viewModel.messages
+                        }
+                    }()
+                    
+                    // Implement windowing - show last 100 messages for performance
+                    let windowedMessages = messages.suffix(100)
+                    
+                    ForEach(Array(windowedMessages), id: \.id) { message in
+                        VStack(alignment: .leading, spacing: 0) {
                             // Check if current user is mentioned
                             let _ = message.mentions?.contains(viewModel.nickname) ?? false
                             
@@ -207,12 +208,12 @@ struct ContentView: View {
                                     
                                     // Check for plain URLs
                                     let urls = message.content.extractURLs()
-                                    ForEach(Array(urls.prefix(3).enumerated()), id: \.offset) { index, urlInfo in
-                                        LazyLinkPreviewView(
-                                            url: urlInfo.url,
-                                            title: nil,
-                                            id: "\(message.id)-\(urlInfo.url.absoluteString)"
-                                        )
+                                    if !urls.isEmpty {
+                                        ForEach(Array(urls.prefix(3).enumerated()), id: \.offset) { index, urlInfo in
+                                            LinkPreviewView(url: urlInfo.url, title: nil)
+                                                .padding(.top, 2)
+                                                .id("\(message.id)-\(urlInfo.url.absoluteString)")
+                                        }
                                     }
                                 }
                             }
@@ -227,13 +228,12 @@ struct ContentView: View {
                                 showMessageActions = true
                             }
                         }
-                        .listRowInsets(EdgeInsets(top: 0, leading: 12, bottom: 0, trailing: 12))
-                        .listRowSeparator(.hidden)
-                        .listRowBackground(backgroundColor)
+                        .padding(.horizontal, 12)
+                        .padding(.vertical, 1)
                     }
+                }
+                .padding(.vertical, 4)
             }
-            .listStyle(.plain)
-            .scrollContentBackground(.hidden)
             .background(backgroundColor)
             .onTapGesture(count: 3) {
                 // Triple-tap to clear current chat
@@ -938,34 +938,6 @@ struct MessageContentView: View {
     }
 }
 
-// Lazy loading wrapper for LinkPreviewView
-struct LazyLinkPreviewView: View {
-    let url: URL
-    let title: String?
-    let id: String
-    
-    @State private var shouldLoad = false
-    
-    var body: some View {
-        Group {
-            if shouldLoad {
-                LinkPreviewView(url: url, title: title)
-                    .padding(.top, 2)
-                    .id(id)
-            }
-        }
-        .onAppear {
-            // Delay loading to improve scroll performance
-            DispatchQueue.main.asyncAfter(deadline: .now() + 0.5) {
-                shouldLoad = true
-            }
-        }
-        .onDisappear {
-            shouldLoad = false
-        }
-    }
-}
-
 // Delivery status indicator view
 struct DeliveryStatusView: View {
     let status: DeliveryStatus