feat: Add testTxQueue function for testing transaction queue

This commit adds the `testTxQueue` function to the internal package. The function sets up a Redis executable and creates two instrumented RESP connections. It then runs a transaction test case, followed by a command test case. This new function will be used for testing the transaction queue functionality.

internal/test_txn_queue.go

@@ -0,0 +1,59 @@
+package internal
+
+import (
+	"fmt"
+
+	"github.com/codecrafters-io/redis-tester/internal/redis_executable"
+	resp_connection "github.com/codecrafters-io/redis-tester/internal/resp/connection"
+	resp_value "github.com/codecrafters-io/redis-tester/internal/resp/value"
+	"github.com/codecrafters-io/redis-tester/internal/resp_assertions"
+
+	"github.com/codecrafters-io/redis-tester/internal/instrumented_resp_connection"
+	"github.com/codecrafters-io/redis-tester/internal/test_cases"
+	"github.com/codecrafters-io/tester-utils/test_case_harness"
+)
+
+func testTxQueue(stageHarness *test_case_harness.TestCaseHarness) error {
+	b := redis_executable.NewRedisExecutable(stageHarness)
+	if err := b.Run(); err != nil {
+		return err
+	}
+
+	logger := stageHarness.Logger
+
+	var clients []*resp_connection.RespConnection
+
+	for i := 0; i < 2; i++ {
+		client, err := instrumented_resp_connection.NewFromAddr(stageHarness, "localhost:6379", fmt.Sprintf("client-%d", i+1))
+		if err != nil {
+			logFriendlyError(logger, err)
+			return err
+		}
+		clients = append(clients, client)
+		defer client.Close()
+	}
+
+	transactionTestCase := test_cases.TransactionTestCase{
+		CommandQueue: [][]string{
+			{"SET", "foo", "41"},
+			{"INCR", "foo"},
+		},
+		ResultArray: []resp_value.Value{},
+	}
+
+	if err := transactionTestCase.RunMulti(clients[0], logger); err != nil {
+		return err
+	}
+
+	if err := transactionTestCase.RunQueueAll(clients[0], logger); err != nil {
+		return err
+	}
+
+	commandTestCase := test_cases.SendCommandTestCase{
+		Command:   "GET",
+		Args:      []string{"foo"},
+		Assertion: resp_assertions.NewNilAssertion(),
+	}
+
+	return commandTestCase.Run(clients[1], logger)
+}