fix: advance last_processed_height in NonMatchingMockWallet

The mock's `process_block_for_wallets` was a no-op, diverging from the real `WalletManager` contract that advances the per-wallet checkpoint for every selected wallet regardless of transaction matches. Sync tests against the mock could pass while production would advance checkpoints. Mirror the contract for selected wallets.

Addresses CodeRabbit review comment on PR #694
#694 (comment)

Author: xdustinface

key-wallet-manager/src/test_utils/mock_wallet.rs

@@ -285,9 +285,12 @@ impl WalletInterface for NonMatchingMockWallet {
     async fn process_block_for_wallets(
         &mut self,
         _block: &Block,
-        _height: u32,
-        _wallets: &BTreeSet<WalletId>,
+        height: u32,
+        wallets: &BTreeSet<WalletId>,
     ) -> BlockProcessingResult {
+        if wallets.contains(&self.wallet_id) && height > self.last_processed_height {
+            self.last_processed_height = height;
+        }
         BlockProcessingResult::default()
     }