Add Built-in Static File Serving Support in Yelix

[GroophyLifefor]

Problem

Currently, Yelix does not provide built-in support for serving static files. Users must manually implement middleware or custom routes to serve assets like HTML, CSS, JS, images, and other static files. This adds extra complexity for users who need a simple way to serve static content.

Proposed Solution

Introduce a built-in static file serving function that allows users to serve a directory with minimal configuration.

Suggested API

const app = new Yelix();

app.serveStatic("./public"); // Serves files from the ./public directory