Not able to load static images in jsp because of "/" servlet mapping

Question

I am working with jsp servlet architecture with maven and I noticed I am not able to load any local images using src attribute.

<img src="img/placeholder.png" class="rounded-circle" alt="..." style="width: 18rem;">

If remote URL is mention then it works fine however I am facing this issue for local images only. As per my observation, main culprit is default PageController I have created using Servlet to deal with navigation requests. The servlet has @WebServlet("/") annotation. Because of this all my src attributes are being pass to this controller as request

http://localhost:8080/SM6MJ/img/placeholder.png

If I change @WebServlet("/") annotation to @WebServlet("/foo") then I am able to load images but then not able to do screen navigation.

Below is my PageController code

@WebServlet(
  name = "PageController",
  description = "Example Servlet Using Annotations",
  urlPatterns = {"/"}
)
public class PageController extends HttpServlet{

    private static final long serialVersionUID = 1L;
    private SongsDAOImpl songDao = SongsDAOImpl.getInstance();
    private static final java.util.logging.Logger LOGGER = java.util.logging.Logger.getLogger(PageController.class.getName());
    
    @Override
    protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        doGet(req, resp);
    }

    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        String action = req.getServletPath();
        try {
            switch (action) {
            case "/dashboard":
                this.navigateToHomeScreen(req, resp);
                break;
            default:
                this.navigateToHomeScreen(req, resp);
            }
        } catch (SQLException e) {
            LOGGER.log(Level.SEVERE, "SQL Error", e);
        }
         
    }

    private void navigateToHomeScreen(HttpServletRequest req, HttpServletResponse resp) throws SQLException,IOException, ServletException {
        req.setAttribute("screen", "dashboard");
        req.getRequestDispatcher("index.jsp").forward(req, resp);
    }

and then in index.jsp I have implemented single page application by including relevant jsps based on setAttribute field called "screen"