chore: remove unused repl-related configuration and placeholder files

repl/examples/bank_account.txt

@@ -0,0 +1,45 @@
+class BankAccount {
+public String holder;
+public double balance;
+public BankAccount(String name, double initial) {
+this.holder = name;
+this.balance = initial;
+}
+public void deposit(double amount) {
+if (amount > 0) {
+this.balance = this.balance + amount;
+}
+}
+public boolean withdraw(double amount) {
+if (amount > 0 && amount <= this.balance) {
+this.balance = this.balance - amount;
+return true;
+}
+return false;
+}
+public double getBalance() {
+return this.balance;
+}
+public String info() {
+return this.holder + ": $" + this.balance;
+}
+}
+
+BankAccount acc = new BankAccount("Alice", 1000.0);
+acc.info()
+acc.getBalance()
+
+acc.deposit(500.0)
+acc.getBalance()
+
+acc.withdraw(200.0)
+acc.getBalance()
+
+acc.withdraw(2000.0)
+acc.getBalance()
+
+acc.info()
+
+%classes
+%whos
+%quit