How do you design a BaseTest class in a Selenium framework?

package base;

import io.github.bonigarcia.wdm.WebDriverManager;
import org.openqa.selenium.WebDriver;
import org.openqa.selenium.chrome.ChromeDriver;
import org.openqa.selenium.chrome.ChromeOptions;
import org.openqa.selenium.firefox.FirefoxDriver;
import org.openqa.selenium.edge.EdgeDriver;
import org.testng.annotations.*;
import java.io.FileInputStream;
import java.time.Duration;
import java.util.Properties;

public class BaseTest {

    // ThreadLocal for parallel execution safety
    private static ThreadLocal<WebDriver> tlDriver = new ThreadLocal<>();

    protected Properties config;

    public static WebDriver getDriver() {
        return tlDriver.get();
    }

    @BeforeSuite
    public void loadConfig() throws Exception {
        config = new Properties();
        FileInputStream fis = new FileInputStream(
            System.getProperty("user.dir") + "/src/test/resources/config.properties"
        );
        config.load(fis);
    }

    @Parameters("browser")
    @BeforeMethod
    public void setUp(@Optional("chrome") String browser) {
        WebDriver driver = createDriver(browser);
        tlDriver.set(driver);

        driver.manage().window().maximize();
        driver.manage().timeouts().implicitlyWait(Duration.ofSeconds(10));
        driver.manage().timeouts().pageLoadTimeout(Duration.ofSeconds(30));
        driver.get(config.getProperty("baseUrl", "https://automateqa.online"));
    }

    private WebDriver createDriver(String browser) {
        return switch (browser.toLowerCase()) {
            case "firefox" -> {
                WebDriverManager.firefoxdriver().setup();
                yield new FirefoxDriver();
            }
            case "edge" -> {
                WebDriverManager.edgedriver().setup();
                yield new EdgeDriver();
            }
            default -> {
                WebDriverManager.chromedriver().setup();
                ChromeOptions opts = new ChromeOptions();
                if (Boolean.parseBoolean(System.getProperty("headless", "false"))) {
                    opts.addArguments("--headless=new", "--no-sandbox",
                                     "--disable-dev-shm-usage", "--window-size=1920,1080");
                }
                yield new ChromeDriver(opts);
            }
        };
    }

    @AfterMethod(alwaysRun = true)
    public void tearDown() {
        if (getDriver() != null) {
            getDriver().quit();
            tlDriver.remove();
        }
    }
}

baseUrl=https://staging.automateqa.online
browser=chrome
headless=false
implicitWait=10
pageLoadTimeout=30

public class LoginTest extends BaseTest {

    @Test
    public void validLoginTest() {
        WebDriver driver = getDriver();
        driver.findElement(By.id("username")).sendKeys("admin");
        driver.findElement(By.id("password")).sendKeys("secret");
        driver.findElement(By.id("loginBtn")).click();

        Assert.assertTrue(driver.getTitle().contains("Dashboard"));
    }
}