fix: use consistent keyClient for all data access

Use self.keyClient.getBackupInfo() instead of KeyClient.live.getBackupInfo()
to maintain consistency with LSP loading and ensure both backup info and LSP
data come from the same source (live or mock) in all app modes.

Author: reez

LDKNodeMonday/App/WalletClient.swift

@@ -52,7 +52,7 @@ public class WalletClient {
 
     func start() async {
         var backupInfo: BackupInfo?
-        backupInfo = try? KeyClient.live.getBackupInfo()
+        backupInfo = try? self.keyClient.getBackupInfo()
 
         if backupInfo != nil {
             do {