key-wallet: expose ManagedWallet.getInfoHandle() for internal use

- Change visibility from private to internal to allow internal helpers to access the opaque FFI handle.
- No functional behavior change.

Author: PastaPastaPasta

packages/swift-sdk/Sources/SwiftDashSDK/KeyWallet/ManagedWallet.swift

@@ -419,9 +419,9 @@ public class ManagedWallet {
         return utxos
     }
 
-    // MARK: - Private Helpers
-    
-    private func getInfoHandle() -> UnsafeMutablePointer<FFIManagedWalletInfo>? {
+    // MARK: - Internal Helpers
+
+    internal func getInfoHandle() -> UnsafeMutablePointer<FFIManagedWalletInfo>? {
         // The handle is an FFIManagedWalletInfo* (opaque C handle)
         return handle
     }