Fix critical room functionality issues

- Fix room field not being copied when creating messageWithPeerID in BluetoothMeshService
- This was causing all room messages to appear in main chat
- Fix room member tracking by ensuring senderPeerID is included
- Change room color from orange to blue to differentiate from private messages
- Clean up room members when peers disconnect to fix member count
- Add debug logging to track room field through message flow

bitchat/Views/ContentView.swift

@@ -215,7 +215,7 @@ struct ContentView: View {
                     }) {
                         Text("\(currentRoom) (\(memberCount))")
                             .font(.system(size: 18, weight: .medium, design: .monospaced))
-                            .foregroundColor(Color.orange)
+                            .foregroundColor(Color.blue)
                     }
                     .buttonStyle(.plain)
                     
@@ -511,7 +511,7 @@ struct ContentView: View {
                                     HStack {
                                         Text(room)
                                             .font(.system(size: 14, design: .monospaced))
-                                            .foregroundColor(viewModel.currentRoom == room ? Color.orange : textColor)
+                                            .foregroundColor(viewModel.currentRoom == room ? Color.blue : textColor)
                                         
                                         Spacer()