Implement a function middlewares(...fns) that composes multiple middleware functions into a single callable function.
Each middleware receives two arguments:

• context: an object shared across all middlewares
• next: a function that calls the next middleware in the chain

The composed function:

• Accepts a context object.
• Returns a Promise.
• Executes middlewares sequentially and asynchronously.
• Stops execution if a middleware does not call next().

This behavior is similar to the middleware system in frameworks like Koa.

Example

async function fn1(ctx, next) {
  ctx.stack.push('fn1-start');
  await next();
  ctx.stack.push('fn1-end');
}

async function fn2(ctx, next) {
  ctx.stack.push('fn2-start');
  await new Promise((resolve) => setTimeout(resolve, 1000));
  await next();
  ctx.stack.push('fn2-end');
}

function fn3(ctx, next) {
  ctx.stack.push('fn3-start');
  next();
  ctx.stack.push('fn3-end');
}

const composedFn = middlewares(fn1, fn2, fn3);

const context = { stack: [] };
await composedFn(context);

console.log(context.stack);
// ['fn1-start', 'fn2-start', 'fn3-start', 'fn3-end', 'fn2-end', 'fn1-end']