feat: add advanced multithreading banking system skeleton

src/main/java/dev/banking/service/BankingSystem.java

@@ -0,0 +1,34 @@
+package dev.banking.service;
+
+import dev.banking.model.*;
+import dev.banking.processor.TransactionProcessor;
+
+import java.util.List;
+import java.util.concurrent.ExecutorService;
+
+public class BankingSystem {
+
+    private final ExecutorService executor;
+    private final TransactionProcessor processor;
+
+    public BankingSystem(
+            ExecutorService executor,
+            TransactionProcessor processor
+    ) {
+        this.executor = executor;
+        this.processor = processor;
+    }
+
+    public void processTransactions(
+            List<Transaction> transactions
+    ) {
+
+        for (Transaction tx : transactions) {
+
+            executor.submit(() -> {
+                processor.process(tx);
+            });
+
+        }
+    }
+}